Receiving State Indication Method for A-MPDU and Receive End Device

ABSTRACT

A receiving state indication method for an aggregate-media access control (MAC) protocol data unit (A-MPDU) and a receiving device, to indicate a receiving state of an A-MPDU including a MAC service data unit (MSDU) fragment. The method includes receiving, by a receive end, an A-MPDU sent by a transmit end; and when determining that at least one MAC protocol data unit (MPDU) in the A-MPDU is obtained by encapsulating a fragment of an MSDU, sending, by the receive end to the transmit end, an acknowledgement frame used to indicate a receiving state of the A-MPDU, where the acknowledgement frame includes a fragment indication field and a receiving state field.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/904,031, filed on Feb. 23, 2018, which is a continuation ofInternational Patent Application No. PCT/CN2016/084576, filed on Jun. 2,2016, which claims priority to Chinese Patent Application No.201510551675.X, filed on Sep. 1, 2015. All of the aforementioned patentapplications are hereby incorporated by reference in their entireties.

TECHNICAL FIELD

The present disclosure relates to the communications field, and inparticular, to a receiving state indication method for anaggregate-media access control (MAC) protocol data unit (A-MPDU) and areceiving device.

BACKGROUND

A fragmentation technology is introduced in the 802.11b protocol thatsupports low rate data transmission. The so-called fragmentationtechnology means that a MAC service data unit (MSDU) or a MAC managementprotocol data unit (MMPDU) is split into multiple segments at a MAClayer, and each segment is referred to as a fragment of the MSDU or theMMPDU. When receiving of a fragment fails, only the fragment that failsto be received is allowed to be retransmitted in the fragmentationtechnology, and there is no need to retransmit the entire MSDU or MMPDU,thereby improving robustness and a throughput rate of a network.

To support a higher data transmission rate, an A-MPDU technology isintroduced in the 802.11n protocol. The A-MPDU technology means that anMSDU or an aggregate-MSDU (A-MSDU) is encapsulated to obtain a MACprotocol data unit (MPDU), and multiple MPDUs are transmitted in anaggregate manner. Aggregated MPDUs are distinguished using MPDUdelimiters. In one A-MPDU, a maximum of 64 encapsulated MSDUs areallowed to aggregate for transmission. In the A-MPDU technology, areceiving state of an A-MPDU is fed back using a block acknowledgement(BA) frame. Each bit in a BA bitmap included in the BA framecorrespondingly indicates a receiving state of one MSDU or A-MSDU. Afirst bit in the BA bitmap correspondingly indicates a receiving stateof an MSDU with a first sequence number (SN) in a BA starting sequencecontrol field, and so on.

In the 802.11ax protocol in a new generation wireless local area network(WLAN) system, an orthogonal frequency division multiple access (OFDMA)technology is introduced. Multiple users who use the OFDMA technologytransmit data on different subchannels. As shown in FIG. 1, multiplestations (STAs) transmit A-MPDUs on corresponding subchannels. Each MPDUin the A-MPDUs is obtained by encapsulating one MSDU or one A-MSDU, andcannot be obtained by encapsulating a fragment of an MSDU. The multipleSTAs use pad bits to enable data transmitted by the multiple STAs toalign in terms of time. Then, a resource occupied by the pad bit may beused to transmit a fragment of an MSDU or an A-MSDU in order to improvetransmission efficiency. Therefore, the new generation WLAN system needsto support both the MSDU fragmentation technology and the A-MPDUtechnology. That is, an MPDU in an A-MPDU may be obtained byencapsulating an MSDU or an A-MSDU, or may be obtained by encapsulatingan MSDU fragment or an A-MSDU fragment. For ease of description, an MSDUfragment in the following description may also be understood as anA-MSDU fragment.

Because an existing compressed BA frame can only indicate a receivingstate of an A-MPDU including MPDUs obtained by encapsulating only MSDUs,and cannot indicate a receiving state of an A-MPDU including an MPDUthat is obtained by encapsulating an MSDU fragment in the new generationWLAN system. Currently, a receiving state of an A-MPDU including an MPDUobtained by encapsulating an MSDU fragment in the new generation WLANsystem can be indicated using the following two solutions. However,there are some disadvantages, and details are as follows.

Solution 1: A manner of allocating an SN of an MSDU is changed.

A unique SN is allocated to an MSDU or an MSDU fragment. In this way,different fragments of a same MSDU no longer have a same SN, and haverespective SNs. Two bits in a sequence control field of an MPDU are usedto indicate MSDU fragments that belong to a same MSDU. Each bit in acompressed BA frame is used to indicate a receiving state of an MSDU oran MSDU fragment corresponding to one SN. Therefore, a receive endindicates a receiving state of an A-MPDU by sending a compressed BAframe to a transmit end. In solution 1, an existing manner of allocatingan SN of an MSDU is changed, and the solution is relatively complex.Once an indication of bits used to indicate MSDU fragments that belongto a same MSDU is incorrect, a receiver incorrectly considers thatfragments coming from multiple MSDUs belong to a same MSDU.

Solution 2: A quantity of fragments of a same MSDU is restricted in anA-MPDU.

It is stipulated that one A-MPDU may include fragments of multipleMSDUs, but one A-MPDU can include only one fragment of a same MSDU. Inthis way, each bit in a compressed BA frame can indicate a receivingstate of an MSDU or an MSDU fragment according to an SN sequence.Therefore, a receive end indicates a receiving state of an A-MPDU bysending a compressed BA frame to a transmit end. Therefore, in solution2, multiple fragments of a same MSDU are not allowed to aggregate in oneA-MPDU for transmission.

In conclusion, a receiving state of an A-MPDU including an MSDU fragmentcannot be well indicated using existing solutions, and the existingsolutions have some disadvantages.

SUMMARY

The present disclosure provides a receiving state indication method foran A-MPDU, a receiving state indication method for an MSDU fragment, areceiving device, and a sending device in order to indicate a receivingstate of an A-MPDU including an MSDU fragment.

Specific technical solutions provided in the embodiments of the presentdisclosure are as follows.

According to a first aspect, an embodiment of the present disclosureprovides a receiving state indication method for an A-MPDU, includingreceiving, by a receive end, an A-MPDU sent by a transmit end, andsending, by the receive end to the transmit end, an acknowledgementframe used to indicate a receiving state of the A-MPDU when at least oneMPDU in the A-MPDU is obtained by encapsulating a fragment of an MSDU,where the acknowledgement frame includes a fragment indication field anda receiving state field, where the fragment indication field is used toindicate that the A-MPDU includes an MPDU obtained by encapsulating anMSDU fragment, the receiving state field is used to indicate a receivingstate of each MPDU in the A-MPDU, a specified bit quantity of bits inthe receiving state field is used to indicate receiving states of MPDUswith a same SN, and each bit in the receiving state field is used toindicate one MPDU in a sequence of SNs in the A-MPDU.

With reference to the first aspect, in a first possible implementationmanner, determining, by the receive end, that at least one MPDU in theA-MPDU is obtained by encapsulating a fragment of an MSDU includesdetermining, by the receive end, that at least one MPDU in the A-MPDU isobtained by encapsulating a fragment of an MSDU when a fragment number(FN) field included in at least one MPDU in the A-MPDU includes not only0.

With reference to the first aspect, in a second possible implementationmanner, when the acknowledgement frame uses a frame format of amulti-user BA (M-BA) frame, the fragment indication field uses the formthat the fragment indication field includes one or more bits of fourreserved bits in a starting sequence control field in a BA informationfield in the M-BA frame, or the fragment indication field includes oneor more bits in a traffic identifier (TID) field in the M-BA frame.

With reference to the first aspect, in a third possible implementationmanner, when the acknowledgement frame uses a frame format of acompressed BA frame, the fragment indication field uses the form thatthe fragment indication field includes one or more bits of four reservedbits in a starting sequence control field in a BA information field inthe compressed BA frame, the fragment indication field includes one ormore bits in a TID field in a BA control field in the compressed BAframe, the fragment indication field includes one or more bits of eightreserved bits in a BA control field in the compressed BA frame, or thefragment indication field includes a Multi-TID bit, a compressed bitmapbit, and a Groupcast with Retries (GCR) bit in a BA control field in thecompressed BA frame.

With reference to the first aspect, in a fourth possible implementationmanner, for the bits in the receiving state field that are used toindicate the receiving states of the MPDUs with the same SN, thespecified bit quantity of the bits is greater than or equal to a maximumvalue of an allowed quantity of MSDU fragments.

According to a second aspect, an embodiment of the present disclosureprovides a receiving device, including a receiving unit configured toreceive an A-MPDU sent by a sending device, a determining unitconfigured to determine an acknowledgement frame used to indicate areceiving state of the A-MPDU when at least one MPDU in the A-MPDUreceived by the receiving unit is obtained by encapsulating a fragmentof an MSDU, and a sending unit configured to send the acknowledgementframe determined by the determining unit to the sending device, wherethe acknowledgement frame includes a fragment indication field and areceiving state field, where the fragment indication field is used toindicate that the A-MPDU includes an MPDU obtained by encapsulating anMSDU fragment, the receiving state field is used to indicate a receivingstate of each MPDU in the A-MPDU, a specified bit quantity of bits inthe receiving state field is used to indicate receiving states of MPDUswith a same SN, and each bit in the receiving state field is used toindicate one MPDU in a sequence of SNs in the A-MPDU.

With reference to the second aspect, in a first possible implementationmanner, when at least one MPDU in the A-MPDU received by the receivingunit is obtained by encapsulating a fragment of an MSDU, the determiningunit is further configured to determine that at least one MPDU in theA-MPDU is obtained by encapsulating a fragment of an MSDU when an FNfield included in at least one MPDU in the A-MPDU includes not only 0.

With reference to the second aspect, in a second possible implementationmanner, when the acknowledgement frame uses a frame format of an M-BAframe, the fragment indication field uses the form that the fragmentindication field includes one or more bits of four reserved bits in astarting sequence control field in a BA information field in the M-BAframe, or the fragment indication field includes one or more bits in aTID field in the M-BA frame.

With reference to the second aspect, in a third possible implementationmanner, when the acknowledgement frame uses a frame format of acompressed BA frame, the fragment indication field uses the form thatthe fragment indication field includes one or more bits of four reservedbits in a starting sequence control field in a BA information field inthe compressed BA frame, the fragment indication field includes one ormore bits in a TID field in a BA control field in the compressed BAframe, the fragment indication field includes one or more bits of eightreserved bits in a BA control field in the compressed BA frame, or thefragment indication field includes a Multi-TID bit, a compressed bitmapbit, and a GCR bit in a BA control field in the compressed BA frame.

With reference to the second aspect, in a fourth possible implementationmanner, for the bits in the receiving state field that are used toindicate the receiving states of the MPDUs with the same SN, thespecified bit quantity of the bits is greater than or equal to a maximumvalue of an allowed quantity of MSDU fragments.

According to a third aspect, an embodiment of the present disclosureprovides a receiving device, including a transceiver configured toreceive an A-MPDU sent by a sending device, and a processor configuredto determine an acknowledgement frame used to indicate a receiving stateof the A-MPDU when at least one MPDU in the A-MPDU received by thetransceiver is obtained by encapsulating a fragment of an MSDU, wherethe transceiver is further configured to send the acknowledgement framedetermined by the processor to the sending device, and theacknowledgement frame includes a fragment indication field and areceiving state field, where the fragment indication field is used toindicate that the A-MPDU includes an MPDU obtained by encapsulating anMSDU fragment, the receiving state field is used to indicate a receivingstate of each MPDU in the A-MPDU, a specified bit quantity of bits inthe receiving state field is used to indicate receiving states of MPDUswith a same SN, and each bit in the receiving state field is used toindicate one MPDU in a sequence of SNs in the A-MPDU.

With reference to the third aspect, in a first possible implementationmanner, when at least one MPDU in the A-MPDU is obtained byencapsulating a fragment of an MSDU, the processor is further configuredto determine that at least one MPDU in the A-MPDU is obtained byencapsulating a fragment of an MSDU when an FN field included in atleast one MPDU in the A-MPDU includes not only 0.

With reference to the third aspect, in a second possible implementationmanner, when the acknowledgement frame uses a frame format of an M-BAframe, the fragment indication field uses the form that the fragmentindication field includes one or more bits of four reserved bits in astarting sequence control field in a BA information field in the M-BAframe, or the fragment indication field includes one or more bits in aTID field in the M-BA frame.

With reference to the third aspect, in a third possible implementationmanner, when the acknowledgement frame uses a frame format of acompressed BA frame, the fragment indication field uses the form thatthe fragment indication field includes one or more bits of four reservedbits in a starting sequence control field in a BA information field inthe compressed BA frame, the fragment indication field includes one ormore bits in a TID field in a BA control field in the compressed BAframe, the fragment indication field includes one or more bits of eightreserved bits in a BA control field in the compressed BA frame, or thefragment indication field includes a Multi-TID bit, a compressed bitmapbit, and a GCR bit in a BA control field in the compressed BA frame.

With reference to the third aspect, in a fourth possible implementationmanner, for the bits in the receiving state field that are used toindicate the receiving states of the MPDUs with the same SN, thespecified bit quantity of the bits is greater than or equal to a maximumvalue of an allowed quantity of MSDU fragments.

According to a fourth aspect, an embodiment of the present disclosureprovides a receiving state indication method for an A-MPDU, includingreceiving, by a receive end, an A-MPDU sent by a transmit end, andsending, by the receive end to the transmit end, an acknowledgementframe used to indicate a receiving state of the A-MPDU, where theacknowledgement frame includes a BA bitmap field, and each bit in the BAbitmap field is used to indicate a receiving state of one MPDU in theA-MPDU.

With reference to the fourth aspect, in a first possible implementationmanner, the acknowledgement frame further includes an A-MPDUidentification field, and the A-MPDU identification field is used by thetransmit end to distinguish between the A-MPDU and another A-MPDU sentby the transmit end.

With reference to the first possible implementation manner of the fourthaspect, in a second possible implementation manner of the fourth aspect,the A-MPDU identification field includes an SN and an FN that areincluded in a first MPDU in the A-MPDU.

According to a fifth aspect, an embodiment of the present disclosureprovides a receiving device, including a receiving unit configured toreceive an A-MPDU sent by a sending device, a determining unitconfigured to determine an acknowledgement frame used to indicate areceiving state of the A-MPDU received by the receiving unit, where theacknowledgement frame includes a BA bitmap field, and each bit in the BAbitmap field is used to indicate a receiving state of one MPDU in theA-MPDU, and a sending unit configured to send the acknowledgement framedetermined by the determining unit to the sending device.

With reference to the fifth aspect, in a first possible implementationmanner, the acknowledgement frame further includes an A-MPDUidentification field, and the A-MPDU identification field is used by thesending device to distinguish between the A-MPDU and another A-MPDU sentby the sending device.

With reference to the first possible implementation manner of the fifthaspect, in a second possible implementation manner of the fifth aspect,the A-MPDU identification field includes an SN and an FN that areincluded in a first MPDU in the A-MPDU.

According to a sixth aspect, an embodiment of the present disclosureprovides a receiving device, including a transceiver configured toreceive an A-MPDU sent by a sending device, and a processor configuredto determine an acknowledgement frame used to indicate a receiving stateof the A-MPDU received by the transceiver, where the acknowledgementframe includes a BA bitmap field, and each bit in the BA bitmap field isused to indicate a receiving state of one MPDU in the A-MPDU, where thetransceiver is further configured to send the acknowledgement framedetermined by the processor to the sending device.

With reference to the sixth aspect, in a first possible implementationmanner, the acknowledgement frame further includes an A-MPDUidentification field, and the A-MPDU identification field is used by thesending device to distinguish between the A-MPDU and another A-MPDU sentby the sending device.

With reference to the first possible implementation manner of the sixthaspect, in a second possible implementation manner of the sixth aspect,the A-MPDU identification field includes an SN and an FN that areincluded in a first MPDU in the A-MPDU.

According to a seventh aspect, an embodiment of the present disclosureprovides a receiving state indication method for an MSDU fragment,including sending, by a transmit end to a receive end, an A-MPDUincluding an MSDU fragment, sending, by the transmit end, a requestframe to the receive end, where the request frame is used to request toindicate a receiving state of the MSDU fragment included in the A-MPDU,and receiving, by the transmit end, a response frame sent by the receiveend, where the response frame is used to indicate the receiving state ofthe MSDU fragment included in the A-MPDU.

With reference to the seventh aspect, in a first possible implementationmanner, the request frame includes an SN of the MSDU fragment, and theresponse frame includes the SN of the MSDU fragment and an indicationfield used to indicate the receiving state of the MSDU fragment.

With reference to the seventh aspect, in a second possibleimplementation manner, when the transmit end sends A-MPDUs includingMSDU fragments to multiple receive ends, the request frame is used torequest the multiple receive ends to separately send a response frame tothe transmit end, where the request frame includes information about anassociation between an identity of each receive end of the multiplereceive ends and an SN of an MSDU fragment received by the receive end.

With reference to the seventh aspect, in a third possible implementationmanner, when the transmit end sends all fragments of an MSDU to thereceive end using at least one A-MPDU, the request frame sent by thetransmit end is used to request to indicate a receiving state of eachfragment in the MSDU, and the response frame received by the transmitend is used to indicate the receiving state of each fragment in theMSDU.

According to an eighth aspect, an embodiment of the present disclosureprovides a receiving state indication method for an MSDU fragment,including receiving, by a receive end, an A-MPDU that includes an MSDUfragment and that is sent by a transmit end, receiving, by the receiveend, a request frame sent by the transmit end, where the request frameis used to request to indicate a receiving state of the MSDU fragmentincluded in the A-MPDU, and sending, by the receive end, a responseframe to the transmit end, where the response frame is used to indicatethe receiving state of the MSDU fragment included in the A-MPDU.

With reference to the eighth aspect, in a first possible implementationmanner, the request frame includes an SN of the MSDU fragment, and theresponse frame includes the SN of the MSDU fragment and an indicationfield used to indicate the receiving state of the MSDU fragment.

With reference to the eighth aspect, in a second possible implementationmanner, when the transmit end sends A-MPDUs including MSDU fragments tomultiple receive ends, the request frame is used to request the multiplereceive ends to separately send a response frame to the transmit end,where the request frame includes SNs of MSDU fragments respectivelyreceived by the multiple receive ends.

With reference to the eighth aspect, in a third possible implementationmanner, when the receive end receives all fragments of an MSDU that aresent by the transmit end using at least one A-MPDU, the request framereceived by the receive end is used to request to indicate a receivingstate of each fragment in the MSDU, and the response frame sent by thereceive end to the transmit end is used to indicate the receiving stateof each fragment in the MSDU.

According to a ninth aspect, an embodiment of the present disclosureprovides a sending device, including a sending unit configured to sendan A-MPDU including an MSDU fragment to a receiving device, and send arequest frame to the receiving device, where the request frame is usedto request to indicate a receiving state of the MSDU fragment includedin the A-MPDU, and a receiving unit configured to receive a responseframe sent by the receiving device, where the response frame is used toindicate the receiving state of the MSDU fragment included in the A-MPDUsent by the sending unit.

With reference to the ninth aspect, in a first possible implementationmanner, the request frame includes an SN of the MSDU fragment, and theresponse frame includes the SN of the MSDU fragment and an indicationfield used to indicate the receiving state of the MSDU fragment.

With reference to the ninth aspect, in a second possible implementationmanner, when the sending unit sends A-MPDUs including MSDU fragments tomultiple receiving devices, the request frame is used to request themultiple receiving devices to separately send a response frame to thesending device, where the request frame includes information about anassociation between an identity of each receiving device of the multiplereceiving devices and an SN of an MSDU fragment received by thereceiving device.

With reference to the ninth aspect, in a third possible implementationmanner, when the sending unit sends all fragments of an MSDU to thereceiving device using at least one A-MPDU, the request frame sent bythe sending unit is used to request to indicate a receiving state ofeach fragment in the MSDU, and the response frame received by thereceiving unit is used to indicate the receiving state of each fragmentin the MSDU.

According to a tenth aspect, an embodiment of the present disclosureprovides a receiving device, including a receiving unit configured toreceive an A-MPDU that includes an MSDU fragment and that is sent by asending device, and receive a request frame sent by the sending device,where the request frame is used to request to indicate a receiving stateof the MSDU fragment included in the A-MPDU, a determining unitconfigured to determine a response frame, where the response frame isused to indicate the receiving state of the MSDU fragment included inthe A-MPDU received by the receiving unit, and a sending unit configuredto send the response frame determined by the determining unit to thesending device.

With reference to the tenth aspect, in a first possible implementationmanner, the request frame includes an SN of the MSDU fragment, and theresponse frame includes the SN of the MSDU fragment and an indicationfield used to indicate the receiving state of the MSDU fragment.

With reference to the tenth aspect, in a second possible implementationmanner, when the sending device sends A-MPDUs including MSDU fragmentsto multiple receiving devices, the request frame received by thereceiving unit is used to request the multiple receiving devices toseparately send a response frame to the sending device, where therequest frame includes SNs of MSDU fragments respectively received bythe multiple receiving devices.

With reference to the tenth aspect, in a third possible implementationmanner, when the receiving unit receives all fragments of an MSDU thatare sent by the sending device using at least one A-MPDU, the requestframe received by the receiving unit is used to request to indicate areceiving state of each fragment in the MSDU, and the response framesent by the sending unit to the sending device is used to indicate thereceiving state of each fragment in the MSDU.

According to an eleventh aspect, an embodiment of the present disclosureprovides a sending device, including a transceiver configured to send anA-MPDU including an MSDU fragment to a receiving device, send a requestframe to the receiving device, where the request frame is used torequest to indicate a receiving state of the MSDU fragment included inthe A-MPDU, and receive a response frame sent by the receiving device,where the response frame is used to indicate the receiving state of theMSDU fragment included in the A-MPDU.

With reference to the eleventh aspect, in a first possibleimplementation manner, the request frame includes an SN of the MSDUfragment, and the response frame includes the SN of the MSDU fragmentand an indication field used to indicate the receiving state of the MSDUfragment.

With reference to the eleventh aspect, in a second possibleimplementation manner, when the transceiver sends A-MPDUs including MSDUfragments to multiple receiving devices, the request frame is used torequest the multiple receiving devices to separately send a responseframe to the sending device, where the request frame includesinformation about an association between an identity of each receivingdevice of the multiple receiving devices and an SN of an MSDU fragmentreceived by the receiving device.

With reference to the eleventh aspect, in a third possibleimplementation manner, when the transceiver sends all fragments of anMSDU to the receiving device using at least one A-MPDU, the requestframe sent by the transceiver is used to request to indicate a receivingstate of each fragment in the MSDU, and the response frame received bythe transceiver is used to indicate the receiving state of each fragmentin the MSDU.

According to a twelfth aspect, an embodiment of the present disclosureprovides a receiving device, including a transceiver configured toreceive an A-MPDU that includes an MSDU fragment and that is sent by asending device, and receive a request frame sent by the sending device,where the request frame is used to request to indicate a receiving stateof the MSDU fragment included in the A-MPDU, and a processor configuredto determine a response frame, where the response frame is used toindicate the receiving state of the MSDU fragment included in the A-MPDUreceived by the transceiver, where the transceiver is further configuredto send the response frame determined by the processor to the sendingdevice.

With reference to the twelfth aspect, in a first possible implementationmanner, the request frame includes an SN of the MSDU fragment, and theresponse frame includes the SN of the MSDU fragment and an indicationfield used to indicate the receiving state of the MSDU fragment.

With reference to the twelfth aspect, in a second possibleimplementation manner, when the sending device sends A-MPDUs includingMSDU fragments to multiple receiving devices, the request frame receivedby the transceiver is used to request the multiple receiving devices toseparately send a response frame to the sending device, where therequest frame includes SNs of MSDU fragments respectively received bythe multiple receiving devices.

With reference to the twelfth aspect, in a third possible implementationmanner, when the receiving device receives all fragments of an MSDU thatare sent by the sending device using at least one A-MPDU, the requestframe received by the receiving device is used to request to indicate areceiving state of each fragment in the MSDU, and the response framesent by the receiving device to the sending device is used to indicatethe receiving state of each fragment in the MSDU.

According to a thirteenth aspect, an embodiment of the presentdisclosure provides a receiving state indication method for an A-MPDU,including allocating, by a transmit end, an SN to each MPDU in anA-MPDU, sending, by the transmit end, the A-MPDU to a receive end, whereeach MPDU in the A-MPDU carries the SN of each MPDU, and receiving, bythe transmit end, an acknowledgement frame sent by the receive end,where the acknowledgement frame includes an indication field used toindicate a receiving state of each MPDU in the A-MPDU, and each bit inthe indication field is used to indicate one MPDU in a sequence of SNsin the A-MPDU.

With reference to the thirteenth aspect, in a first possibleimplementation manner, the allocating, by a transmit end, an SN to eachMPDU in an A-MPDU includes allocating, by the transmit end, the SN toeach MPDU in the A-MPDU when at least one MPDU in the A-MPDU is obtainedby encapsulating a fragment of an MSDU.

With reference to the thirteenth aspect, in a second possibleimplementation manner, the SN is carried in a MAC header of the MPDU.

With reference to the thirteenth aspect, in a third possibleimplementation manner, when the acknowledgement frame uses a frameformat of a compressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

With reference to the thirteenth aspect, in a fourth possibleimplementation manner, the acknowledgement frame further includes afragment indication field, and the fragment indication field is used toindicate that at least one MPDU in the A-MPDU is obtained byencapsulating a fragment of an MSDU.

According to a fourteenth aspect, an embodiment of the presentdisclosure provides a receiving state indication method for an A-MPDU,including receiving, by a receive end, an A-MPDU sent by a transmit end,where each MPDU in the A-MPDU carries an SN of each MPDU, and sending,by the receive end, an acknowledgement frame to the transmit end, wherethe acknowledgement frame includes an indication field used to indicatea receiving state of each MPDU in the A-MPDU, and each bit in theindication field is used to indicate one MPDU in a sequence of MPDU SNsin the A-MPDU.

With reference to the fourteenth aspect, in a first possibleimplementation manner, the SN is carried in a MAC header of the MPDU.

With reference to the fourteenth aspect, in a second possibleimplementation manner, when the acknowledgement frame uses a frameformat of a compressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

With reference to the fourteenth aspect, in a third possibleimplementation manner, before the sending, by the receive end, anacknowledgement frame to the transmit end, the method further includesdetermining, by the receive end, that at least one MPDU in the A-MPDU isobtained by encapsulating a fragment of an MSDU when each MPDU in theA-MPDU carries the SN of each MPDU, where the acknowledgement framefurther includes a fragment indication field, and the fragmentindication field is used to indicate that at least one MPDU in theA-MPDU is obtained by encapsulating a fragment of an MSDU.

According to a fifteenth aspect, an embodiment of the present disclosureprovides a sending device, including an allocation unit configured toallocate an SN to each MPDU in an A-MPDU, a sending unit configured tosend the A-MPDU to a receiving device, where each MPDU in the A-MPDUcarries the SN allocated by the allocation unit, and a receiving unitconfigured to receive an acknowledgement frame sent by the receivingdevice, where the acknowledgement frame includes an indication fieldused to indicate a receiving state of each MPDU in the A-MPDU sent bythe sending unit, and each bit in the indication field is used toindicate one MPDU in a sequence of SNs in the A-MPDU.

With reference to the fifteenth aspect, in a first possibleimplementation manner, the allocation unit is further configured toallocate the SN to each MPDU in the A-MPDU when at least one MPDU in theA-MPDU is obtained by encapsulating a fragment of an MSDU.

With reference to the fifteenth aspect, in a second possibleimplementation manner, the SN is carried in a MAC header of the MPDU.

With reference to the fifteenth aspect, in a third possibleimplementation manner, when the acknowledgement frame uses a frameformat of a compressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

With reference to the fifteenth aspect, in a fourth possibleimplementation manner, the acknowledgement frame further includes afragment indication field, and the fragment indication field is used toindicate that at least one MPDU in the A-MPDU is obtained byencapsulating a fragment of an MSDU.

According to a sixteenth aspect, an embodiment of the present disclosureprovides a receiving device, including a receiving unit configured toreceive an A-MPDU sent by a sending device, where each MPDU in theA-MPDU carries an SN of each MPDU, a determining unit configured todetermine an acknowledgement frame, where the acknowledgement frameincludes an indication field used to indicate a receiving state of eachMPDU in the A-MPDU received by the receiving unit, and each bit in theindication field is used to indicate one MPDU in a sequence of MPDU SNsin the A-MPDU, and a sending unit configured to send the acknowledgementframe determined by the determining unit to the sending device.

With reference to the sixteenth aspect, in a first possibleimplementation manner, the SN is carried in a MAC header of the MPDU.

With reference to the sixteenth aspect, in a second possibleimplementation manner, when the acknowledgement frame uses a frameformat of a compressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

With reference to the sixteenth aspect, in a third possibleimplementation manner, the acknowledgement frame determined by thedetermining unit further includes a fragment indication field, and thefragment indication field is used to indicate that at least one MPDU inthe A-MPDU is obtained by encapsulating a fragment of an MSDU.

According to a seventeenth aspect, an embodiment of the presentdisclosure provides a sending device, including a processor configuredto allocate an SN to each MPDU in an A-MPDU, and a transceiverconfigured to send the A-MPDU to a receiving device, where each MPDU inthe A-MPDU carries the SN allocated by the processor, and receive anacknowledgement frame sent by the receiving device, where theacknowledgement frame includes an indication field used to indicate areceiving state of each MPDU in the A-MPDU, and each bit in theindication field is used to indicate one MPDU in a sequence of SNs inthe A-MPDU.

With reference to the seventeenth aspect, in a first possibleimplementation manner, the processor is further configured to allocatethe SN to each MPDU in the A-MPDU when at least one MPDU in the A-MPDUis obtained by encapsulating a fragment of an MSDU.

With reference to the seventeenth aspect, in a second possibleimplementation manner, the SN is carried in a MAC header of the MPDU.

With reference to the seventeenth aspect, in a third possibleimplementation manner, when the acknowledgement frame uses a frameformat of a compressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

With reference to the seventeenth aspect, in a fourth possibleimplementation manner, the acknowledgement frame further includes afragment indication field, and the fragment indication field is used toindicate that at least one MPDU in the A-MPDU is obtained byencapsulating a fragment of an MSDU.

According to an eighteenth aspect, an embodiment of the presentdisclosure provides a receiving device, including a transceiverconfigured to receive an A-MPDU sent by a sending device, where eachMPDU in the A-MPDU carries an SN of each MPDU, and a processorconfigured to determine an acknowledgement frame, where theacknowledgement frame includes an indication field used to indicate areceiving state of each MPDU in the A-MPDU received by the transceiver,and each bit in the indication field is used to indicate one MPDU in asequence of MPDU SNs in the A-MPDU, where the transceiver is furtherconfigured to send the acknowledgement frame determined by the processorto the sending device.

With reference to the eighteenth aspect, in a first possibleimplementation manner, the SN is carried in a MAC header of the MPDU.

With reference to the eighteenth aspect, in a second possibleimplementation manner, when the acknowledgement frame uses a frameformat of a compressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

With reference to the eighteenth aspect, in a third possibleimplementation manner, the acknowledgement frame determined by theprocessor further includes a fragment indication field, and the fragmentindication field is used to indicate that at least one MPDU in theA-MPDU is obtained by encapsulating a fragment of an MSDU.

A receiving state of an A-MPDU including an MSDU fragment can beindicated using the four technical solutions provided in the embodimentsof the present disclosure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of data transmission using an OFDMAtechnology;

FIG. 2 is a schematic structural diagram of a sequence control field inan MPDU according to an embodiment of the present disclosure;

FIG. 3 is a schematic flowchart of a receiving state indication methodfor an A-MPDU according to an embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of a per TID information fieldin an M-BA frame according to an embodiment of the present disclosure;

FIG. 5 is a schematic structural diagram of a BA control field in acompressed BA frame according to an embodiment of the presentdisclosure;

FIG. 6 is a schematic structural diagram of a compressed BA frameaccording to an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of data transmission using an OFDMAtechnology according to an embodiment of the present disclosure;

FIG. 8 is a schematic diagram of a receiving indication field of a firstBA frame according to an embodiment of the present disclosure;

FIG. 9 is a schematic diagram of a receiving indication field of a firstBA frame according to an embodiment of the present disclosure;

FIG. 10 is a schematic diagram of a receiving indication field of asecond BA frame according to an embodiment of the present disclosure;

FIG. 11 is a schematic flowchart of a receiving state indication methodfor an A-MPDU according to an embodiment of the present disclosure;

FIG. 12 is a schematic diagram of a BA bitmap field in a BA frameaccording to an embodiment of the present disclosure;

FIG. 13 is a schematic flowchart of a receiving state indication methodfor an MSDU fragment according to an embodiment of the presentdisclosure;

FIG. 14 is a schematic diagram of a frame format of a request frameaccording to an embodiment of the present disclosure;

FIG. 15 is a schematic diagram of a frame format of a response frameaccording to an embodiment of the present disclosure;

FIG. 16 is a schematic diagram of data transmission using an OFDMAtechnology according to an embodiment of the present disclosure;

FIG. 17 is a schematic flowchart of a receiving state indication methodfor an A-MPDU according to an embodiment of the present disclosure;

FIG. 18 is a schematic structural diagram of a high throughput (HT)control field according to an embodiment of the present disclosure;

FIG. 19 is a schematic structural diagram of a quality of service (QoS)control field according to an embodiment of the present disclosure;

FIG. 20 is a schematic diagram of data transmission using an OFDMAtechnology according to an embodiment of the present disclosure;

FIG. 21 is a schematic structural diagram of a receiving deviceaccording to an embodiment of the present disclosure;

FIG. 22 is a schematic structural diagram of a receiving deviceaccording to an embodiment of the present disclosure;

FIG. 23 is a schematic structural diagram of a receiving deviceaccording to an embodiment of the present disclosure;

FIG. 24 is a schematic structural diagram of a receiving deviceaccording to an embodiment of the present disclosure;

FIG. 25 is a schematic structural diagram of a sending device accordingto an embodiment of the present disclosure;

FIG. 26 is a schematic structural diagram of a receiving deviceaccording to an embodiment of the present disclosure;

FIG. 27 is a schematic structural diagram of a sending device accordingto an embodiment of the present disclosure;

FIG. 28 is a schematic structural diagram of a receiving deviceaccording to an embodiment of the present disclosure;

FIG. 29 is a schematic structural diagram of a sending device accordingto an embodiment of the present disclosure;

FIG. 30 is a schematic structural diagram of a receiving deviceaccording to an embodiment of the present disclosure;

FIG. 31 is a schematic structural diagram of a sending device accordingto an embodiment of the present disclosure; and

FIG. 32 is a schematic structural diagram of a receiving deviceaccording to an embodiment of the present disclosure.

DESCRIPTION OF EMBODIMENTS

The following clearly describes the technical solutions in theembodiments of the present disclosure with reference to the accompanyingdrawings in the embodiments of the present disclosure. The describedembodiments are merely some but not all of the embodiments of thepresent disclosure. All other embodiments obtained by persons ofordinary skill in the art based on the embodiments of the presentdisclosure without creative efforts shall fall within the protectionscope of the present disclosure.

Embodiments of the present disclosure provide a receiving stateindication method for an A-MPDU, a receiving state indication method foran MSDU fragment, a sending device, and a receiving device in order toindicate a receiving state of an A-MPDU including an MSDU fragment. Themethods and the devices are based on a same inventive concept. Because aproblem-resolving principle of the methods is similar to that of thedevices, mutual reference may be made to implementation of the devicesand implementation of the methods, and no repeated description isprovided.

The present disclosure relates to a technology for transmitting anA-MPDU including an MSDU fragment. The technology for transmitting anA-MPDU including an MSDU fragment means that a transmit end transmitsmultiple MPDUs to a receive end by aggregating the MPDUs. AggregatedMPDUs are distinguished using MPDU delimiters. Each MPDU may be obtainedby encapsulating an MSDU or an MSDU fragment. The MSDU fragment is asegment of an MSDU. All fragments except a last fragment need to have anequal length and include even-numbered bytes. Optionally, whether anMSDU is equally fragmented is not limited in the present disclosure. AnMPDU header of an MPDU includes a sequence control field. As shown inFIG. 2, the sequence control field includes an SN and an FN. The SN isused to identify an MSDU encapsulated in the MPDU or an MSDU to which anMSDU fragment belongs. Each MSDU corresponds to one SN. The FN is usedto identify an MSDU fragment encapsulated in the MPDU. MSDU fragmentsthat belong to a same MSDU are respectively corresponding to differentFNs. In a process of transmitting an A-MPDU including an MSDU fragment,if transmission of a fragment fails, the fragment is allowed to beretransmitted, and there is no need to retransmit an MSDU to which thefragment belongs, thereby improving robustness and a throughput rate ofa network system.

In the embodiments of the present disclosure, an A-MSDU or an A-MSDUfragment may also be encapsulated in an MPDU. The A-MSDU fragment is asegment of an A-MSDU. For ease of description, an MSDU fragment in thefollowing embodiments may be understood as an A-MSDU fragment.

A receiving state of an A-MPDU including an MSDU fragment can beindicated using the technical solutions provided in the embodiments ofthe present disclosure. Details are as follows.

Embodiment 1

As shown in FIG. 3, this embodiment of the present disclosure provides areceiving state indication method for an A-MPDU, including the followingsteps.

Step S301: A receive end receives an A-MPDU sent by a transmit end.

Step S302: When at least one MPDU in the A-MPDU is obtained byencapsulating a fragment of an MSDU, the receive end sends, to thetransmit end, an acknowledgement frame used to indicate a receivingstate of the A-MPDU, where the acknowledgement frame includes a fragmentindication field and a receiving state field. The fragment indicationfield is used to indicate that the A-MPDU includes an MPDU obtained byencapsulating an MSDU fragment. The fragment indication field is used todistinguish a type of the acknowledgement frame. The receiving statefield is used to indicate a receiving state of each MPDU in the A-MPDU.A specified bit quantity of bits in the receiving state field is used toindicate receiving states of MPDUs with a same SN. Each bit in thereceiving state field is used to indicate one MPDU in a sequence of SNsin the A-MPDU.

The acknowledgement frame in this embodiment may be a BA frame. Tofacilitate distinction between the acknowledgement frame and an existingBA frame, in the following content, the acknowledgement frame in thisembodiment is described as a first BA frame, and the existing BA frameis described as a second BA frame.

In this embodiment, when all MPDUs in the A-MPDU are obtained byencapsulating MSDUs, the receive end uses a second BA frame (an existingBA frame) to indicate a receiving state of the A-MPDU. A specific methodincludes that when all MPDUs in the A-MPDU are obtained by encapsulatingMSDUs, the receive end sends, to the transmit end, a second BA frameused to indicate a receiving state of the A-MPDU.

The second BA frame includes a fragment indication field and a receivingstate field. The fragment indication field is used to indicate that theA-MPDU indicated by the second BA frame does not include an MPDUobtained by encapsulating an MSDU fragment. Each bit in the receivingstate field is used to indicate a receiving state of one MPDU in asequence of SNs in the A-MPDU.

A major difference between the first BA frame and the second BA framelies in that the first BA frame is used to indicate a receiving state ofan A-MPDU including an MSDU fragment, and the second BA frame is used toindicate a receiving state of an A-MPDU that does not include an MSDUfragment, and the first BA frame is a new BA frame provided in thisembodiment, and the second BA frame is an existing BA frame. In thisembodiment, fragment indication fields are used to distinguish betweenthe first BA frame and the second BA frame.

In step S302 in this embodiment, the receive end may determine,according to an FN field carried in an MPDU in the A-MPDU, whether theA-MPDU includes an MSDU fragment. The FN field is carried in a sequencecontrol field of an MPDU header of the MPDU.

When all FN fields in MPDUs in the A-MPDU include 0, it indicates thatthe A-MPDU does not include an MSDU fragment. When an FN field in atleast one MPDU in the A-MPDU does not include 0, it indicates that theA-MPDU includes an MSDU fragment. Therefore, when the receive enddetermines that an FN field carried in at least one MPDU in the A-MPDUsent by the transmit end includes not only 0, the receive end determinesthat the at least one MPDU in the A-MPDU is obtained by encapsulating afragment of an MSDU. That is, the receive end determines that the A-MPDUsent by the transmit end includes an MSDU fragment. In this case, thereceive end selects a first BA frame to indicate the receiving state ofthe A-MPDU.

In this embodiment, the transmit end uses fragment indication fields todistinguish between the first BA frame and the second BA frame. Thefirst BA frame and the second BA frame may use a frame format of an M-BAframe or a frame format of a compressed BA frame. The compressed BAframe may be transmitted in a multi-user manner, for example, multipleuser multiple-input multiple-output (MU-MIMO) or OFDMA, or may betransmitted in a single user manner. The fragment indication field mayuse the following form according to different frame formats used by thefirst BA frame and the second BA frame.

1. The frame format of the M-BA frame or the frame format of thecompressed BA frame is used.

Both a BA information field in the M-BA frame and a BA information fieldin the compressed BA frame include a starting sequence control field.The starting sequence control field includes four reserved bits. Thefragment indication field may include one or more bits of the fourreserved bits to indicate that the BA frame is a first BA frame or asecond BA frame.

2. The frame format of the M-BA frame or the frame format of thecompressed BA frame is used.

Both the M-BA frame and the compressed BA frame include a TID field withfour bits. The fragment indication field may include one or more bits inthe TID field to indicate that the BA frame is a first BA frame or asecond BA frame.

The fragment indication field includes one bit in the TID field. Becauseonly three bits in the TID field are used in a currently used enhanceddistributed channel access (EDCA) mechanism, the fragment indicationfield may use the remaining one bit in the TID field to indicate thatthe BA frame is a first BA frame or a second BA frame.

The fragment indication field includes multiple bits in the TID field.The fragment indication field includes multiple bits in the TID field toindicate a particular TID value. The particular TID value is used toindicate that the BA frame is a first BA frame or a second BA frame. Forexample, when the fragment indication field includes the four bits inthe TID field, a TID value that may be indicated by the four bits rangesfrom 0 to 15, and a particular TID value indicated by the fragmentindication field may be an integer in a range from 8 to 15.

For the M-BA frame, as shown in FIG. 4, the TID field is located in aper TID information (Per TID Info) field in a BA information field inthe M-BA frame. The field may also be referred to as a per associationidentifier information (Per AID Info) field. Each Per TID Info fieldincludes an association identifier (AID) field, a BA/acknowledgementpolicy (BA/ACK policy) indication field, and a TID field. For thecompressed BA frame, the TID field is located in a BA control field inthe compressed BA frame.

3. The frame format of the compressed BA frame is used.

FIG. 5 shows a structure of a BA control field in a compressed BA frame.The fragment indication field includes one or more bits of eightreserved bits in the BA control field in the compressed BA frame.

4. The frame format of the compressed BA frame is used.

The fragment indication field includes a Multi-TID bit, a compressedbitmap bit, and a GCR bit in a BA control field in the compressed BAframe. For example, as shown in the following Table 1, the fragmentindication field includes a corresponding Multi-TID bit, compressedbitmap bit, and GCR bit in Table 1 when a BA frame variant is“reserved”.

TABLE 1 Compressed Multi-TID bit bitmap bit GCR bit BA frame variant 0 00 Basic BA 0 1 0 Compressed 1 0 0 Extended compressed BA 1 1 0 Multi-TIDBA 0 0 1 Reserved 0 1 1 GCR BA 1 0 1 Reserved 1 1 1 Reserved

In this embodiment, the first BA frame includes a fragment indicationfield and a receiving state field. The receiving state field is used toindicate a receiving state of each MPDU in the A-MPDU. A specified bitquantity of bits in the receiving state field is used to indicatereceiving states of MPDUs with a same SN. Each bit in the receivingstate field is used to indicate one MPDU in a sequence of SNs in theA-MPDU. Optionally, for the bits in the receiving state field that areused to indicate the receiving states of the MPDUs with the same SN, thespecified bit quantity of the bits is greater than or equal to a maximumvalue of an allowed quantity of MSDU fragments.

For example, the first BA frame uses a structure of a compressed BAframe shown in FIG. 6. The receiving state field is a BA bitmap field inthe compressed BA frame in FIG. 6. The BA bitmap field includes eightbytes (that is, 64 bits). It is assumed that a maximum value of anallowed quantity of MSDU fragments is 4, and the BA bitmap field usesevery four bits to indicate receiving states of MPDUs with a same SN. Ifan MPDU is obtained by encapsulating an MSDU, four bits corresponding toan SN of the MPDU are used to jointly indicate a receiving state of theMPDU, or one bit of the four bits may be selected to indicate thereceiving state of the MPDU. Optionally, a first bit of the four bits isselected to indicate the receiving state of the MPDU, and three otherbits of the four bits are padded with 0. If an MPDU is obtained byencapsulating an MSDU fragment, four bits corresponding to an SN of theMPDU respectively indicate receiving states of four MPDUs. The fourMPDUs are obtained by respectively encapsulating four MSDU fragmentswith the same SN. If a total quantity of fragments of the MSDU is n,where n is less than 4, n bits of four bits are selected to indicatereceiving states of MPDUs obtained by respectively encapsulating the nMSDU fragments. Optionally, first n bits of the four bits are selectedto indicate the receiving states of the MPDUs obtained by respectivelyencapsulating the n MSDU fragments, and remaining bits are padded with0.

Downlink OFDMA transmission is used as an example. Assuming that a bitis set to 1, it indicates that a receiving state is success, andassuming that a bit is set to 0, it indicates that a receiving state isfailure. As shown in FIG. 7, an access point (AP) sends downlink data inan OFDMA transmission manner. The AP transmits three A-MPDUs to a STA 1.An A-MPDU 1 includes three MPDUs, where an MPDU 1 and an MPDU 2 areobtained by respectively encapsulating an MSDU 1 and an MSDU 2, and anMPDU 3 is obtained by encapsulating a fragment 1 of an MSDU 3, and theSTA 1 successfully receives the MPDU 1 and the MPDU 2, and fails toreceive the MPDU 3. An A-MPDU 2 includes three MPDUs, where an MPDU 4 isobtained by encapsulating the retransmitted fragment 1 of the MSDU 3, anMPDU 5 is obtained by encapsulating a fragment 2 of the MSDU 3, and anMPDU 6 is obtained by encapsulating an MSDU 4, and the STA 1successfully receives the MPDU 4 and the MPDU 6, and fails to receivethe MPDU 5. An A-MPDU 3 includes two MPDUs, where an MPDU 7 and an MPDU8 are obtained by respectively encapsulating an MSDU 5 and an MSDU 6,and the STA 1 successfully receives the MPDU 7 and the MPDU 8. Becausethe fragment 1 of the MSDU 3 and the fragment 2 of the MSDU 3 belong tothe same MSDU 3, the fragment 1 and the fragment 2 have a same SN.

The STA 1 sends first BA frames to the AP to indicate a receiving stateof the A-MPDU 1 and a receiving state of the A-MPDU 2. One first BAframe is used to indicate the receiving state of the A-MPDU 1. An SN ina starting sequence control field in the one first BA frame is 1 (an SNis usually indicated using 12 bits). A receiving state field of the onefirst BA frame is shown in FIG. 8. The other first BA frame is used toindicate the receiving state of the A-MPDU 2. An SN in a startingsequence control field in the other first BA frame is 3. A receivingstate field of the other first BA frame is shown in FIG. 9. The STAsends a second BA frame to the AP to indicate a receiving state of theA-MPDU 3. An SN in a starting sequence control field in the second BAframe is 5. A receiving state field of the second BA frame is shown inFIG. 10.

As shown in FIG. 7, after receiving the A-MPDU, the receive endimmediately sends the first BA frame to the transmit end. It should benoted that in a case of a possible delay of the first BA frame, afterreceiving the A-MPDU, the receive end may delay a period of time beforesending the first BA frame to the transmit end.

In Embodiment 1, after a receive end receives an A-MPDU sent by atransmit end, and when at least one MPDU in the A-MPDU is obtained byencapsulating a fragment of an MSDU, the receive end sends, to thetransmit end, a first BA frame used to indicate a receiving state of theA-MPDU, where the first BA frame includes a fragment indication fieldand a receiving state field, the fragment indication field is used toindicate that the A-MPDU includes an MPDU that is obtained byencapsulating an MSDU fragment, the receiving state field is used toindicate a receiving state of each MPDU in the A-MPDU, a specified bitquantity of bits in the receiving state field is used to indicatereceiving states of MPDUs with a same SN, and each bit in the receivingstate field is used to indicate one MPDU in a sequence of SNs in theA-MPDU. A receiving state of an A-MPDU including an MSDU fragment can beindicated using the method provided in Embodiment 1.

Embodiment 2

As shown in FIG. 11, this embodiment of the present disclosure providesa receiving state indication method for an A-MPDU, including thefollowing steps.

Step S1101: A receive end receives an A-MPDU sent by a transmit end.

Step S1102: The receive end sends, to the transmit end, anacknowledgement frame used to indicate a receiving state of the A-MPDU,where the acknowledgement frame includes a BA bitmap field, and each bitin the BA bitmap field is used to indicate a receiving state of one MPDUin the A-MPDU.

In this embodiment, the acknowledgement frame may be a BA frame. Theacknowledgement frame is described as a BA frame in the followingcontent. The BA frame may use a frame format of a compressed BA frameshown in FIG. 6, or may use a frame format of an M-BA frame. A frameformat of a compressed BA frame is used as an example. A BA bitmap fieldin the compressed BA frame includes 64 bits (eight bytes). If each bitin the BA bitmap field is used to indicate a receiving state of one MPDUin an A-MPDU, the BA bitmap field can indicate receiving states of amaximum of 64 MPDUs in the A-MPDU.

For example, downlink OFDMA transmission is used as an example. Assumingthat a bit is set to 1, it indicates that a receiving state is success,and assuming that a bit is set to 0, it indicates that a receiving stateis failure. As shown in FIG. 7, an AP sends downlink data in an OFDMAtransmission manner. The AP transmits three A-MPDUs to a STA 1. AnA-MPDU 1 includes three MPDUs, where an MPDU 1 and an MPDU 2 areobtained by respectively encapsulating an MSDU 1 and an MSDU 2, and anMPDU 3 is obtained by encapsulating a fragment 1 of an MSDU 3, and theSTA 1 successfully receives the MPDU 1 and the MPDU 2, and fails toreceive the MPDU 3. An A-MPDU 2 includes three MPDUs, where an MPDU 4 isobtained by encapsulating the retransmitted fragment 1 of the MSDU 3, anMPDU 5 is obtained by encapsulating a fragment 2 of the MSDU 3, and anMPDU 6 is obtained by encapsulating an MSDU 4, and the STA 1successfully receives the MPDU 4 and the MPDU 6, and fails to receivethe MPDU 5. An A-MPDU 3 includes two MPDUs, where an MPDU 7 is obtainedby encapsulating the retransmitted fragment 2 of the MSDU 3, and an MPDU8 is obtained by encapsulating the MSDU 4, and the STA 1 successfullyreceives the MPDU 7 and the MPDU 8. Because the fragment 1 of the MSDU 3and the fragment 2 of the MSDU 3 belong to the same MSDU 3, the fragment1 and the fragment 2 have a same SN. The STA 1 needs to send three BAframes to the AP. The three acknowledgement frames are used torespectively indicate receiving states of the three A-MPDUs. A BA bitmapfield in a BA frame used to indicate a receiving state of the A-MPDU 1is shown in FIG. 12. Likewise, a BA bitmap field in a BA frame used toindicate a receiving state of the second A-MPDU includes 101 . . . (64bits in total), and a BA bitmap field in a BA frame used to indicate areceiving state of the third A-MPDU includes 11 . . . (64 bits intotal).

Because the receive end may delay sending the BA frame, after thetransmit end sends the A-MPDU, the BA frame indicating the A-MPDU doesnot necessarily reach the transmit end immediately. If all first MPDUsin multiple A-MPDUs are obtained by encapsulating different fragments ofa same MSDU, the first MPDUs in the multiple A-MPDUs have a same SN. Forexample, first MPDUs in the A-MPDU 2 and the A-MPDU 3 in the foregoingexample have a same SN, and in this case, the transmit end needs todistinguish a BA frame used to indicate a receiving state of an A-MPDU.

In this embodiment, in consideration of a possible delay of the BAframe, the BA frame sent by the receive end to the transmit end furtherincludes an A-MPDU identification field. The A-MPDU identification fieldis used by the transmit end to distinguish an A-MPDU acknowledged by theacknowledgement frame.

Optionally, the A-MPDU identification field in the BA frame includes anSN and an FN that are included in a first MPDU in the A-MPDU indicatedby the BA frame. The SN is located in last 12 bits in a startingsequence field in the BA frame (the other approaches). The FN is locatedin first four reserved bits in the starting sequence field in the BAframe (the method provided in this embodiment, which is different fromthe other approaches). The transmit end may distinguish betweendifferent A-MPDUs according to SNs and FNs that are carried in A-MPDUidentification fields.

It should be noted that, in this embodiment, content of the A-MPDUidentification field in the BA frame is not limited to the contentdescribed above. The A-MPDU identification field may also include othercontent provided that the transmit end can distinguish, according to thecontent of the A-MPDU identification field in the BA frame, an A-MPDUwhose receiving state is indicated by the BA frame.

Technical solutions in Embodiment 2 may be combined with technicalsolutions in Embodiment 1 for use.

In Embodiment 2, after a receive end receives an A-MPDU sent by atransmit end, the receive end sends, to the transmit end, anacknowledgement frame used to indicate a receiving state of the A-MPDU,where the acknowledgement frame includes a BA bitmap field, and each bitin the BA bitmap field is used to indicate a receiving state of one MPDUin the A-MPDU. A receiving state of an A-MPDU including an MSDU fragmentcan be indicated using the method provided in Embodiment 2. Theacknowledgement frame may be a first BA frame in Embodiment 1, and isused to indicate a receiving state of an A-MPDU including an MSDUfragment.

Embodiment 3

As shown in FIG. 13, this embodiment of the present disclosure providesa receiving state indication method for an MSDU fragment. A process ofinteraction between a transmit end and a receive end is as follows.

Step S1301: The transmit end sends an A-MPDU including an MSDU fragmentto the receive end.

Step S1302: The transmit end sends a request frame to the receive end,where the request frame is used to request to indicate a receiving stateof the MSDU fragment in the A-MPDU.

Step S1303: The receive end sends a response frame to the transmit end,where the response frame is used to indicate the receiving state of theMSDU fragment in the A-MPDU.

In this embodiment, after the transmit end sends the A-MPDU including anMSDU fragment to the receive end, the receive end indicates, to thetransmit end using an existing BA frame, a receiving state of an MPDUthat is obtained by encapsulating an MSDU and that is in the A-MPDU. TheBA frame does not indicate a receiving state of an MPDU that is obtainedby encapsulating an MSDU fragment and that is in the A-MPDU. When thetransmit end sends the request frame to the receive end to request toindicate the receiving state of the MSDU fragment, the receive endindicates the receiving state of the MSDU fragment using the responseframe.

It should be noted that an occasion for sending a request frame is notlimited in this embodiment. The transmit end may send, after sending anA-MPDU including an MSDU fragment, a request frame to the receive end.In this case, the request frame is used to request to indicate areceiving state of the MSDU fragment in the A-MPDU. The transmit end maysend, after sending multiple A-MPDUs including MSDU fragments, a requestframe to the receive end. In this case, the request frame is used torequest to indicate receiving states of the MSDU fragments in themultiple A-MPDUs. The transmit end sends a request frame after sendingall fragments of an MSDU to the receive end. A specific method includesthat when the transmit end sends all fragments of an MSDU to the receiveend using at least one A-MPDU, the transmit end sends a request frame tothe receive end, where the request frame is used to request to indicatea receiving state of each fragment in the MSDU, and the receive endsends a response frame to the transmit end, where the response frame isused to indicate the receiving state of each fragment in the MSDU.

It should be noted that a manner of sending the request frame and theresponse frame is not limited in this embodiment. Downlink datatransmission is used as an example. An AP may send a request frame usingdownlink OFDMA, and a STA may send a response frame using uplink OFDMA.Uplink data transmission is used as an example. A STA may send a requestframe using uplink OFDMA contention-based random access, and the uplinkOFDMA contention-based random access transmission needs to be triggeredby an AP by sending a trigger frame. The STA may send a request frameusing uplink OFDMA scheduling, and the uplink OFDMA schedulingtransmission also needs to be triggered by the AP by sending a triggerframe. In this embodiment, the request frame and the response frame mayalso be sent in a MU-MIMO manner.

In this embodiment, the request frame includes an SN of the MSDUfragment. A frame format of a request frame shown in FIG. 14 is used asan example. The SN of the MSDU fragment is carried in an SN field in asequence control field. The receive end can learn, according to the SNcarried in the request frame, a receiving state that is of a fragment ofan MSDU corresponding to the SN and that the transmit end wants torequest to indicate. A request frame sent by an AP may be for multipleSTAs. A structure of the request frame is shown in FIG. 14. A receivingaddress (RA) is a broadcast address, a sequence control field includessequence control subfields of the multiple STAs, and each subfieldincludes a STA identity and an SN. The STA identity may be an AIDallocated by the AP to the STA. Optionally, the request frame sent bythe AP includes resource allocation indication information and/or an FN,where the resource allocation indication information indicates asubchannel or a frequency resource block on which the STA replies with aresponse frame, and may further include a parameter, such as amodulation and coding scheme (MCS) used by the STA to transmit a BA.

In this embodiment, the response frame includes the SN of the MSDUfragment and an indication field used to indicate the receiving state ofthe MSDU fragment. A frame format of a response frame shown in FIG. 15is used as an example. The SN of the MSDU fragment is carried in an SNfield in a sequence control field, the indication field is a fragmentbitmap field, and a length of the indication field may be set accordingto a requirement. When the length of the indication field is eight bits,the indication field can indicate receiving states of a maximum of eightMSDU fragments. Each bit is used to indicate a receiving state of oneMSDU fragment, and so on.

For example, assuming that a bit is set to 1, it indicates that areceiving state is success, and assuming that a bit is set to 0, itindicates that a receiving state is failure. Downlink OFDMA datatransmission shown in FIG. 16 is used as an example. An AP sends data inan OFDMA transmission manner. The AP transmits two A-MPDUs to a STA 1.An A-MPDU 1 includes three MPDUs, where an MPDU 1 and an MPDU 2 areobtained by respectively encapsulating an MSDU 1 and an MSDU 2, and anMPDU 3 is obtained by encapsulating a fragment 1 of an MSDU 3, and theSTA 1 successfully receives the MPDU 1, the MPDU 2, and the MPDU 3. AnA-MPDU 2 includes four MPDUs, where an MPDU 4 is obtained byencapsulating a fragment 2 of the MSDU 3, an MPDU 5 is obtained byencapsulating a fragment 3 of the MSDU 3, and an MPDU 6 and an MPDU 7are obtained by respectively encapsulating an MSDU 4 and an MSDU 5, andthe STA 1 fails to receive the MPDU 4, and successfully receives theMPDU 5, the MPDU 6, and the MPDU 7. The STA 1 needs to send two BAframes to the AP. A first BA frame indicates receiving states of onlythe MPDU 1 and the MPDU 2 in the A-MPDU 1. A second BA frame indicatesreceiving states of only the MPDU 6 and the MPDU 7 in the A-MPDU 2. Arequest frame sent by the AP to the STA 1 carries an SN of the MSDU 3,and is used to request to indicate receiving states of the fragment 1,the fragment 2, and the fragment 3 of the MSDU 3. A response frame sentby the STA 1 to the AP carries the SN of the MSDU 3, and an indicationfield is 101. The first bit indicates that the fragment 1 of the MSDU 3is successfully received, the second bit indicates that receiving of thefragment 2 of the MSDU 3 fails, and the third bit indicates that thefragment 3 of the MSDU 3 is successfully received.

In this embodiment, when the transmit end sends A-MPDUs including MSDUfragments to multiple receive ends, the request frame sent by thetransmit end may be used to request the multiple receive ends toseparately reply to the transmit end with a response frame. The requestframe includes information about an association between an identity ofeach receiving device of multiple receiving devices and an SN of an MSDUfragment received by the receiving device. For example, as shown in FIG.14, a sequence control field in a request frame includes informationabout an association between an identity of each STA of multiple receiveends from a STA 1 to a STA n and an SN of an MSDU fragment correspondingto the STA. The multiple STAs separately use a frame format shown inFIG. 15 to reply to an AP with a response frame.

In Embodiment 3, a transmit end sends an A-MPDU including an MSDUfragment to a receive end. The transmit end sends a request frame to thereceive end, where the request frame is used to request to indicate areceiving state of the MSDU fragment in the A-MPDU, and the receive endsends a response frame to the transmit end, where the response frame isused to indicate the receiving state of the MSDU fragment in the A-MPDU.A receiving state of an MSDU fragment in an A-MPDU can be indicatedusing the technical solutions provided in Embodiment 3.

Embodiment 4

As shown in FIG. 17, this embodiment of the present disclosure providesa receiving state indication method for an A-MPDU. A process ofinteraction between a transmit end and a receive end is as follows.

Step S1701: The transmit end allocates an SN to each MPDU in an A-MPDU.

Step S1702: The transmit end sends the A-MPDU to the receive end, whereeach MPDU in the A-MPDU carries the SN of each MPDU.

Step S1703: The receive end sends a BA/ACK frame to the transmit end,where the acknowledgement frame includes an indication field used toindicate a receiving state of each MPDU in the A-MPDU, and each bit inthe indication field is used to indicate one MPDU in a sequence of MPDUSNs in the A-MPDU.

In this embodiment, optionally, when at least one MPDU in the A-MPDU isobtained by encapsulating a fragment of an MSDU, the transmit endallocates the SN to each MPDU in the A-MPDU. In this way, the transmitend is prevented from allocating SNs to MPDUs in all A-MPDUs, andworkload of the transmit end is reduced.

The acknowledgement frame in this embodiment may be a BA frame. Tofacilitate distinction between the acknowledgement frame and an existingBA frame, in the following content, the acknowledgement frame in thisembodiment is described as a first BA frame, and the existing BA frameis described as a second BA frame. The SN allocated by the transmit endto each MPDU in the A-MPDU is carried in a MAC header of the MPDU. TheSN is temporarily allocated by the transmit end to the MPDU. A preferredimplementation manner is that the receive end indicates, to the transmitend, a receiving state of an A-MPDU including an MSDU fragment usingonly an MPDU SN. The MPDU may carry the SN in the following severalmanners.

Manner 1: The SN of the MPDU may be carried in a HT rate control fieldof the MAC header. FIG. 18 shows a schematic structural diagram of an HTcontrol field. A reserved field in the HT control field is used toindicate that the field is an HT control field of this generation WLANsystem. Several bits of 28 bits in other content fields may be used toindicate a temporary SN of the MPDU. Alternatively, an access categoryconstraint (AC constraint) indication bit and a reverse directiongrant/more physical layer convergence procedure protocol data unit(RDG/More PPDU) indication bit in the HT control field may be used toindicate the SN of the MPDU. Because one A-MPDU includes a maximum of 64MPDUs, five bits are preferably used to indicate a SN of an MPDU.

Manner 2: The SN of the MPDU may be carried in a QoS control field ofthe MAC header. FIG. 19 shows a schematic structural diagram of a QoScontrol field. Several bits of eight bits in a transmit opportunity(TXOP) limit field/queue size field/reserved control field may be usedto indicate the SN of the MPDU. Optionally, any bit other than the eightbits in the QoS control field is used to indicate that the QoS controlfield carries the SN of the MPDU.

In this embodiment, the first BA frame (a BA frame provided in thisembodiment) is used to indicate a receiving state of an A-MPDU includingan MSDU fragment, and the second BA frame (an existing BA frame) is usedto indicate a receiving state of an A-MPDU that does not include an MSDUfragment. In this embodiment, when the receive end determines that FNfields of all MPDUs in the received A-MPDU include only 0, it indicatesthat the A-MPDU does not include an MSDU fragment. In this case, thereceive end feeds back a receiving state of each MPDU in the A-MPDU tothe transmit end using the second BA frame. This is specified in theother approaches, and details are not described herein.

To distinguish between the first BA frame and the second BA frame, boththe first BA frame and the second BA frame further include a fragmentindication field. A fragment indication field in the first BA frame isused to indicate that at least one MPDU in an A-MPDU indicated by thefirst BA frame is obtained by encapsulating a fragment of an MSDU. Afragment indication field in the second BA frame is used to indicatethat all MPDUs in an A-MPDU indicated by the second BA frame areobtained by encapsulating MSDUs. The receive end may determine, using afragment indication field in a BA frame, whether an A-MPDU indicated bythe BA frame includes an MSDU fragment. A specific form used by thefragment indication fields in the first BA frame and the second BA frameis as follows.

1. A frame format of an M-BA frame or a frame format of a compressed BAframe is used.

Both a BA information field in the M-BA frame and a BA information fieldin the compressed BA frame include a starting sequence control field.The starting sequence control field includes four reserved bits. Thefragment indication field may include one or more bits of the fourreserved bits to indicate whether an A-MPDU indicated by the BA frameincludes an MSDU fragment.

2. A frame format of an M-BA frame or a frame format of a compressed BAframe is used.

Both the M-BA frame and the compressed BA frame include a TID field withfour bits. The fragment indication field may include one or more bits inthe TID field, to indicate whether an A-MPDU indicated by the BA frameincludes an MSDU fragment.

The fragment indication field includes one bit in the TID field. Becauseonly three bits in the TID field are used in a currently used EDCAmechanism, the fragment indication field may use the remaining one bitin the TID field to indicate whether an A-MPDU indicated by the BA frameincludes an MSDU fragment.

The fragment indication field includes multiple bits in the TID field.The fragment indication field includes multiple bits in the TID field toindicate a particular TID value. The particular TID value is used toindicate whether an A-MPDU indicated by the BA frame includes an MSDUfragment. For example, when the fragment indication field includes fourbits in the TID field, a TID value that may be indicated by the fourbits ranges from 0 to 15, and a particular TID value indicated by thefragment indication field may be an integer in a range from 8 to 15.

For the M-BA frame, as shown in FIG. 4, the TID field is located in aPer TID info field in a BA information field in the M-BA frame. Each PerTID Info field includes an AID field, a BA/ACK policy indication field,and a TID field. For the compressed BA frame, the TID field is locatedin a BA control field in the compressed BA frame.

3. A frame format of a compressed BA frame is used.

FIG. 5 shows a structure of a BA control field in a compressed BA frame.The fragment indication field includes one or more bits of eightreserved bits in the BA control field in the compressed BA frame.

4. A frame format of a compressed BA frame is used.

The fragment indication field includes a Multi-TID bit, a compressedbitmap bit, and a GCR bit in a BA control field in the compressed BAframe. For example, as shown in the following Table 2, the fragmentindication field includes a corresponding Multi-TID bit, compressedbitmap bit, and GCR bit in Table 2 when a BA frame variant is“reserved”. In this case, the BA frame is used to indicate that anA-MPDU includes an MSDU fragment.

TABLE 2 Compressed Multi-TID bit bitmap bit GCR bit BA frame variant 0 00 Basic BA 0 1 0 Compressed BA 1 0 0 Extended compressed BA 1 1 0Multi-TID BA 0 0 1 Reserved 0 1 1 GCR BA 1 0 1 Reserved 1 1 1 Reserved

In this embodiment, the first BA frame may use the frame format of thecompressed BA frame. The indication field included in the BA frame is aBA bitmap field in the compressed BA frame. Each bit in the BA bitmapfield is used to indicate one MPDU in a sequence of MPDU SNs in theA-MPDU.

For example, assuming that a bit is set to 1, it indicates that areceiving state is success, and assuming that a bit is set to 0, itindicates that a receiving state is failure. Downlink OFDMA datatransmission shown in FIG. 20 is used as an example. An AP sends data inan OFDMA transmission manner. The AP transmits two A-MPDUs to a STA 1.An A-MPDU 1 includes three MPDUs, where an MPDU 1, an MPDU 2, and anMPDU 3 are obtained by respectively encapsulating an MSDU 1, an MSDU 2,and an MSDU 3, and the STA 1 successfully receives the MPDU 1, the MPDU2, and the MPDU 3. An A-MPDU 2 includes four MPDUs, where an MPDU 4 isobtained by encapsulating a fragment 1 of an MSDU 4, an MPDU 5 isobtained by encapsulating a fragment 2 of the MSDU 4, and an MPDU 6 andan MPDU 7 are obtained by respectively encapsulating an MSDU 5 and anMSDU 6, and the STA 1 fails to receive the MPDU 4, and successfullyreceives the MPDU 5, the MPDU 6, and the MPDU 7. Because the A-MPDU 2includes an MSDU fragment, the AP allocates SNs to all MPDUs in theA-MPDU 2. It is assumed that SNs respectively corresponding to the MPDU4 to the MPDU 7 are 1 to 4.

The STA 1 sends two BA frames to the AP. A first sent BA frame is asecond BA frame (an existing BA frame), and is used to indicate areceiving state of each MPDU in a sequence of SNs in the A-MPDU 1. Astarting SN is 1. It is assumed that a length of an indication field forreceiving states is 64 bits, and an SN in a starting field in the firstBA frame is 1, and the indication field is 111 . . . (64 bits in total).First three bits are used to sequentially indicate receiving states ofthe MPDU 1 to the MPDU 3, and other bits are padded with 0. A secondsent BA frame is a first BA frame (a BA frame provided in thisembodiment), and is used to indicate a receiving state of each MPDU in asequence of MPDU SNs in the A-MPDU 2. It is assumed that a length of anindication field for receiving states is 64 bits, and an SN in astarting field in the second BA frame is 4, and the indication field is0111 . . . (64 bits in total). First four bits are used to sequentiallyindicate receiving states of the MPDU 4 to the MPDU 7, and other bitsare padded with 0.

In Embodiment 4, when at least one MPDU in an A-MPDU is obtained byencapsulating a fragment of an MSDU, a transmit end allocates an SN toeach MPDU in the A-MPDU. The transmit end sends the A-MPDU to a receiveend, where each MPDU in the A-MPDU carries the SN of each MPDU, and thereceive end sends a BA frame to the transmit end, where the BA frameincludes an indication field used to indicate a receiving state of eachMPDU in the A-MPDU, and each bit in the indication field is used toindicate one MPDU in a sequence of MPDU SNs in the A-MPDU. A receivingstate of an A-MPDU including an MSDU fragment can be indicated using thetechnical solutions provided in Embodiment 4.

Embodiment 5

Based on Embodiment 1, the present disclosure further provides areceiving device. The receiving device may use the method provided inthe embodiment corresponding to FIG. 3. Referring to FIG. 21, areceiving device 2100 includes a receiving unit 2101, a determining unit2102, and a sending unit 2103.

The receiving unit 2101 is configured to receive an A-MPDU sent by asending device.

The determining unit 2102 is configured to determine an acknowledgementframe used to indicate a receiving state of the A-MPDU when at least oneMPDU in the A-MPDU received by the receiving unit 2101 is obtained byencapsulating a fragment of an MSDU.

The sending unit 2103 is configured to send the acknowledgement framedetermined by the determining unit 2102 to the sending device.

The acknowledgement frame includes a fragment indication field and areceiving state field. The fragment indication field is used to indicatethat the A-MPDU includes an MPDU obtained by encapsulating an MSDUfragment. The receiving state field is used to indicate a receivingstate of each MPDU in the A-MPDU. A specified bit quantity of bits inthe receiving state field is used to indicate receiving states of MPDUswith a same SN. Each bit in the receiving state field is used toindicate one MPDU in a sequence of SNs in the A-MPDU.

Optionally, when at least one MPDU in the A-MPDU received by thereceiving unit 2101 is obtained by encapsulating a fragment of an MSDU,the determining unit 2102 is further configured to determine that atleast one MPDU in the A-MPDU is obtained by encapsulating a fragment ofan MSDU when an FN field included in at least one MPDU in the A-MPDUincludes not only 0.

Optionally, when the acknowledgement frame uses a frame format of anM-BA frame, the fragment indication field uses the form that thefragment indication field includes one or more bits of four reservedbits in a starting sequence control field in a BA information field inthe M-BA frame, or the fragment indication field includes one or morebits in a TID field in the M-BA frame.

Optionally, when the acknowledgement frame uses a frame format of acompressed BA frame, the fragment indication field uses the form thatthe fragment indication field includes one or more bits of four reservedbits in a starting sequence control field in a BA information field inthe compressed BA frame, the fragment indication field includes one ormore bits in a TID field in a BA control field in the compressed BAframe, the fragment indication field includes one or more bits of eightreserved bits in a BA control field in the compressed BA frame, or thefragment indication field includes a Multi-TID bit, a compressed bitmapbit, and a GCR bit in a BA control field in the compressed BA frame.

Optionally, for the bits in the receiving state field that are used toindicate the receiving states of the MPDUs with the same SN, thespecified bit quantity of the bits is greater than or equal to a maximumvalue of an allowed quantity of MSDU fragments.

It should be noted that unit division in this embodiment of the presentdisclosure is an example, is merely logical function division, and theremay be another division in actual implementation. In addition, functionunits in the embodiments of this application may be integrated into oneprocessing unit, or each of the units may exist alone physically, or twoor more units are integrated into one unit. The integrated unit may beimplemented in a form of hardware, or may be implemented in a form of asoftware function unit.

When the integrated unit is implemented in the form of a softwarefunction unit and sold or used as an independent product, the integratedunit may be stored in a computer-readable storage medium. Based on suchunderstanding, the technical solutions of this application essentially,or the part contributing to the other approaches, or all or some of thetechnical solutions may be implemented in a form of a software product.The computer software product is stored in a storage medium and includesseveral instructions for instructing a computer device (which may be apersonal computer, a server, a network device, or the like) or aprocessor to perform all or some of the steps of the methods in theembodiments of the present application. The foregoing storage mediumincludes any medium that can store program code, such as a universalserial bus (USB) flash drive, a removable hard disk, a read-only memory(ROM), a random access memory (RAM), a magnetic disk, or an opticaldisc.

Based on Embodiment 1, the present disclosure further provides areceiving device 2200. The receiving device 2200 may use the methodprovided in the embodiment corresponding to FIG. 3, and may be a devicethe same as the receiving device 2100 shown in FIG. 21. Referring toFIG. 22, the receiving device 2200 includes a transceiver 2201, aprocessor 2202, a bus 2203, and a memory 2204.

The transceiver 2201, the processor 2202, and the memory 2204 areinterconnected using the bus 2203. The bus 2203 may be a peripheralcomponent interconnect (PCI) bus, an extended industry standardarchitecture (EISA) bus, or the like. The bus 2203 may be classifiedinto an address bus, a data bus, a control bus, and the like. For easeof illustration, only one bold line is used in FIG. 22 to represent thebus 2203, which, however, does not mean that there is only one bus oronly one type of bus.

The transceiver 2201 is configured to receive an A-MPDU sent by asending device.

The processor 2202 is configured to determine an acknowledgement frameused to indicate a receiving state of the A-MPDU when at least one MPDUin the A-MPDU received by the transceiver 2201 is obtained byencapsulating a fragment of an MSDU.

The transceiver 2201 is further configured to send the acknowledgementframe determined by the processor 2202 to the sending device.

The acknowledgement frame includes a fragment indication field and areceiving state field. The fragment indication field is used to indicatethat the A-MPDU includes an MPDU obtained by encapsulating an MSDUfragment. The receiving state field is used to indicate a receivingstate of each MPDU in the A-MPDU. A specified bit quantity of bits inthe receiving state field is used to indicate receiving states of MPDUswith a same SN. Each bit in the receiving state field is used toindicate one MPDU in a sequence of SNs in the A-MPDU.

Optionally, that the processor 2202 determines that at least one MPDU inthe A-MPDU is obtained by encapsulating a fragment of an MSDU includesthat when an FN field included in at least one MPDU in the A-MPDUincludes not only 0, the processor 2202 determines that at least oneMPDU in the A-MPDU is obtained by encapsulating a fragment of an MSDU.

Optionally, when the acknowledgement frame uses a frame format of anM-BA frame, the fragment indication field uses the form that thefragment indication field includes one or more bits of four reservedbits in a starting sequence control field in a BA information field inthe M-BA frame, or the fragment indication field includes one or morebits in a TID field in the M-BA frame.

Optionally, when the acknowledgement frame uses a frame format of acompressed BA frame, the fragment indication field uses the form thatthe fragment indication field includes one or more bits of four reservedbits in a starting sequence control field in a BA information field inthe compressed BA frame, the fragment indication field includes one ormore bits in a TID field in a BA control field in the compressed BAframe, the fragment indication field includes one or more bits of eightreserved bits in a BA control field in the compressed BA frame, or thefragment indication field includes a Multi-TID bit, a compressed bitmapbit, and a GCR bit in a BA control field in the compressed BA frame.

Optionally, for the bits in the receiving state field that are used toindicate the receiving states of the MPDUs with the same SN, thespecified bit quantity of the bits is greater than or equal to a maximumvalue of an allowed quantity of MSDU fragments.

The receiving device 2200 further includes the memory 2204, which isconfigured to store a program and the like. Further, the program mayinclude program code. The program code includes a computer operationinstruction. The memory 2204 may include a RAM, and may further includea non-volatile memory, for example, at least one magnetic disk memory.The processor 2202 executes the application program stored in the memory2204 to implement the receiving state indication method for an A-MPDU.

Embodiment 6

Based on Embodiment 2, the present disclosure further provides areceiving device 2300. The receiving device 2300 may use the methodprovided in the embodiment corresponding to FIG. 11. Referring to FIG.23, the receiving device 2300 includes a receiving unit 2301, adetermining unit 2302, and a sending unit 2303.

The receiving unit 2301 is configured to receive an A-MPDU sent by asending device.

The determining unit 2302 is configured to determine an acknowledgementframe used to indicate a receiving state of the A-MPDU received by thereceiving unit 2301. The acknowledgement frame includes a BA bitmapfield. Each bit in the BA bitmap field is used to indicate a receivingstate of one MPDU in the A-MPDU.

The sending unit 2303 is configured to send the acknowledgement framedetermined by the determining unit 2302 to the sending device.

Optionally, the acknowledgement frame further includes an A-MPDUidentification field. The A-MPDU identification field is used by thesending device to distinguish between the A-MPDU and another A-MPDU sentby the sending device.

Optionally, the A-MPDU identification field includes an SN and an FNthat are included in a first MPDU in the A-MPDU.

It should be noted that unit division in this embodiment of the presentdisclosure is an example, is merely logical function division, and theremay be another division in actual implementation. In addition, functionunits in the embodiments of this application may be integrated into oneprocessing unit, or each of the units may exist alone physically, or twoor more units are integrated into one unit. The integrated unit may beimplemented in a form of hardware, or may be implemented in a form of asoftware function unit.

When the integrated unit is implemented in the form of a softwarefunction unit and sold or used as an independent product, the integratedunit may be stored in a computer-readable storage medium. Based on suchan understanding, the technical solutions of this applicationessentially, or the part contributing to the other approaches, or all orsome of the technical solutions may be implemented in a form of asoftware product. The computer software product is stored in a storagemedium and includes several instructions for instructing a computerdevice (which may be a personal computer, a server, a network device, orthe like) or a processor to perform all or some of the steps of themethods in the embodiments of the present application. The foregoingstorage medium includes any medium that can store program code, such asa USB flash drive, a removable hard disk, a ROM, a RAM, a magnetic disk,or an optical disc.

Based on Embodiment 2, the present disclosure further provides areceiving device 2400. The receiving device 2400 may use the methodprovided in the embodiment corresponding to FIG. 11, and may be a devicethe same as the receiving device 2300 shown in FIG. 23. Referring toFIG. 24, the receiving device 2400 includes a transceiver 2401, aprocessor 2402, a bus 2403, and a memory 2404.

The transceiver 2401, the processor 2402, and the memory 2404 areinterconnected using the bus 2403. The bus 2403 may be a PCI bus, anEISA bus, or the like. The bus may be classified into an address bus, adata bus, a control bus, and the like. For ease of illustration, onlyone bold line is used in FIG. 24 to represent the bus 2403, which,however, does not mean that there is only one bus or only one type ofbus.

The transceiver 2401 is configured to receive an A-MPDU sent by asending device.

The processor 2402 is configured to determine an acknowledgement frameused to indicate a receiving state of the A-MPDU received by thetransceiver 2401. The acknowledgement frame includes a BA bitmap field.Each bit in the BA bitmap field is used to indicate a receiving state ofone MPDU in the A-MPDU.

The transceiver 2401 is further configured to send the acknowledgementframe determined by the processor 2402 to the sending device.

Optionally, the acknowledgement frame further includes an A-MPDUidentification field. The A-MPDU identification field is used by thesending device to distinguish between the A-MPDU and another A-MPDU sentby the sending device.

Optionally, the A-MPDU identification field includes an SN and an FNthat are included in a first MPDU in the A-MPDU.

The receiving device 2400 further includes the memory 2404, which isconfigured to store a program and the like. Further, the program mayinclude program code. The program code includes a computer operationinstruction. The memory 2404 may include a RAM, and may further includea non-volatile memory, for example, at least one disk memory. Theprocessor 2402 executes the application program stored in the memory2404 to implement the receiving state indication method for an A-MPDU.

Embodiment 7

Based on Embodiment 3, the present disclosure further provides a sendingdevice 2500. The sending device 2500 may use the method provided in theembodiment corresponding to FIG. 13. Referring to FIG. 25, the sendingdevice 2500 includes a sending unit 2501 and a receiving unit 2502.

The sending unit 2501 is configured to send an A-MPDU including an MSDUfragment to a receiving device, and send a request frame to thereceiving device. The request frame is used to request to indicate areceiving state of the MSDU fragment included in the A-MPDU.

The receiving unit 2502 is configured to receive a response frame sentby the receiving device. The response frame is used to indicate thereceiving state of the MSDU fragment included in the A-MPDU sent by thesending unit 2501.

Optionally, the request frame includes an SN of the MSDU fragment, andthe response frame includes the SN of the MSDU fragment and anindication field used to indicate the receiving state of the MSDUfragment.

Optionally, when the sending unit 2501 sends A-MPDUs including MSDUfragments to multiple receiving devices, the request frame is used torequest the multiple receiving devices to separately send a responseframe to the sending device. The request frame includes informationabout an association between an identity of each receiving device of themultiple receiving devices and an SN of an MSDU fragment received by thereceiving device.

Optionally, when the sending unit 2501 sends all fragments of an MSDU tothe receiving device using at least one A-MPDU, the request frame sentby the sending unit 2501 is used to request to indicate a receivingstate of each fragment in the MSDU, and the response frame received bythe receiving unit 2502 is used to indicate the receiving state of eachfragment in the MSDU.

Based on Embodiment 3, the present disclosure further provides areceiving device 2600. The receiving device 2600 may use the methodprovided in the embodiment corresponding to FIG. 13. Referring to FIG.26, the receiving device 2600 includes a receiving unit 2601, adetermining unit 2602, and a sending unit 2603.

The receiving unit 2601 is configured to receive an A-MPDU that includesan MSDU fragment and that is sent by a sending device, and receive arequest frame sent by the sending device. The request frame is used torequest to indicate a receiving state of the MSDU fragment included inthe A-MPDU.

The determining unit 2602 is configured to determine a response frame.The response frame is used to indicate the receiving state of the MSDUfragment included in the A-MPDU received by the receiving unit 2601.

The sending unit 2603 is configured to send the response framedetermined by the determining unit 2602 to the sending device.

Optionally, the request frame includes an SN of the MSDU fragment, andthe response frame includes the SN of the MSDU fragment and anindication field used to indicate the receiving state of the MSDUfragment.

Optionally, when the sending device sends A-MPDUs including MSDUfragments to multiple receiving devices, the request frame received bythe receiving unit 2601 is used to request the multiple receivingdevices to separately send a response frame to the sending device. Therequest frame includes SNs of MSDU fragments respectively received bythe multiple receiving devices.

Optionally, when the receiving unit 2601 receives all fragments of anMSDU that are sent by the sending device using at least one A-MPDU, therequest frame received by the receiving unit 2601 is used to request toindicate a receiving state of each fragment in the MSDU, and theresponse frame sent by the sending unit 2603 to the sending device isused to indicate the receiving state of each fragment in the MSDU.

It should be noted that unit division in this embodiment of the presentdisclosure is an example, is merely logical function division, and theremay be another division in actual implementation. In addition, functionunits in the embodiments of this application may be integrated into oneprocessing unit, or each of the units may exist alone physically, or twoor more units are integrated into one unit. The integrated unit may beimplemented in a form of hardware, or may be implemented in a form of asoftware function unit.

When the integrated unit is implemented in the form of a softwarefunction unit and sold or used as an independent product, the integratedunit may be stored in a computer-readable storage medium. Based on suchan understanding, the technical solutions of this applicationessentially, or the part contributing to the other approaches, or all orsome of the technical solutions may be implemented in a form of asoftware product. The computer software product is stored in a storagemedium and includes several instructions for instructing a computerdevice (which may be a personal computer, a server, a network device, orthe like) or a processor to perform all or some of the steps of themethods in the embodiments of the present application. The foregoingstorage medium includes any medium that can store program code, such asa USB flash drive, a removable hard disk, a ROM, a RAM, a magnetic disk,or an optical disc.

Based on Embodiment 3, the present disclosure further provides a sendingdevice 2700. The sending device 2700 may use the method provided in theembodiment corresponding to FIG. 13, and may be a device the same as thesending device 2500 shown in FIG. 25. Referring to FIG. 27, the sendingdevice 2700 includes a transceiver 2701, a bus 2702, and a memory 2703.

The transceiver 2701 and the memory 2703 are interconnected using thebus 2702. The bus 2702 may be a PCI bus, an EISA bus, or the like. Thebus 2702 may be classified into an address bus, a data bus, a controlbus, and the like. For ease of illustration, only one bold line is usedin FIG. 27 to represent the bus 2702, which, however, does not mean thatthere is only one bus or only one type of bus.

The transceiver 2701 is configured to send an A-MPDU including an MSDUfragment to a receiving device, send a request frame to the receivingdevice, where the request frame is used to request to indicate areceiving state of the MSDU fragment included in the A-MPDU, and receivea response frame sent by the receiving device, where the response frameis used to indicate the receiving state of the MSDU fragment included inthe A-MPDU.

Optionally, the request frame includes an SN of the MSDU fragment, andthe response frame includes the SN of the MSDU fragment and anindication field used to indicate the receiving state of the MSDUfragment.

Optionally, when the transceiver 2701 sends A-MPDUs including MSDUfragments to multiple receiving devices, the request frame is used torequest the multiple receiving devices to separately send a responseframe to the sending device. The request frame includes informationabout an association between an identity of each receiving device of themultiple receiving devices and an SN of an MSDU fragment received by thereceiving device.

Optionally, when the transceiver 2701 sends all fragments of an MSDU tothe receiving device using at least one A-MPDU, the request frame sentby the transceiver 2701 is used to request to indicate a receiving stateof each fragment in the MSDU, and the response frame received by thetransceiver 2701 is used to indicate the receiving state of eachfragment in the MSDU.

The sending device 2700 further includes the memory 2703, which isconfigured to store a program and the like. Further, the program mayinclude program code. The program code includes a computer operationinstruction. The memory 2703 may include a RAM, and may further includea non-volatile memory, for example, at least one disk memory.

Based on Embodiment 3, the present disclosure further provides areceiving device 2800. The receiving device 2800 may use the methodprovided in the embodiment corresponding to FIG. 13, and may be a devicethe same as the receiving device 2600 shown in FIG. 26. Referring toFIG. 28, the receiving device 2800 includes a transceiver 2801, aprocessor 2802, a bus 2803, and a memory 2804.

The transceiver 2801, the processor 2802, and the memory 2804 areinterconnected using the bus 2803. The bus 2803 may be a PCI bus, anEISA bus, or the like. The bus 2803 may be classified into an addressbus, a data bus, a control bus, and the like. For ease of illustration,only one bold line is used in FIG. 28 to represent the bus 2803, which,however, does not mean that there is only one bus or only one type ofbus.

The transceiver 2801 is configured to receive an A-MPDU that includes anMSDU fragment and that is sent by a sending device, and receive arequest frame sent by the sending device. The request frame is used torequest to indicate a receiving state of the MSDU fragment included inthe A-MPDU.

The processor 2802 is configured to determine a response frame. Theresponse frame is used to indicate the receiving state of the MSDUfragment included in the A-MPDU received by the transceiver 2801.

The transceiver 2801 is further configured to send the response framedetermined by the processor 2802 to the sending device.

Optionally, the request frame includes an SN of the MSDU fragment, andthe response frame includes the SN of the MSDU fragment and anindication field used to indicate the receiving state of the MSDUfragment.

Optionally, when the sending device sends A-MPDUs including MSDUfragments to multiple receiving devices, the request frame is used torequest the multiple receiving devices to separately send a responseframe to the sending device. The request frame includes SNs of MSDUfragments respectively received by the multiple receiving devices.

Optionally, when the transceiver 2801 receives all fragments of an MSDUthat are sent by the sending device using at least one A-MPDU, therequest frame received by the transceiver 2801 is used to request toindicate a receiving state of each fragment in the MSDU, and theresponse frame sent by the transceiver 2801 to the sending device isused to indicate the receiving state of each fragment in the MSDU.

The receiving device 2800 further includes the memory 2804, which isconfigured to store a program and the like. Further, the program mayinclude program code. The program code includes a computer operationinstruction. The memory 2804 may include a RAM, and may further includea non-volatile memory, for example, at least one disk memory. Theprocessor 2802 executes the application program stored in the memory2804 to indicate the receiving state of the MSDU fragment in the A-MPDU.

Embodiment 8

Based on Embodiment 4, the present disclosure further provides a sendingdevice 2900. The sending device 2900 may use the method provided in theembodiment corresponding to FIG. 17. Referring to FIG. 29, the sendingdevice 2900 includes an allocation unit 2901, a sending unit 2902, and areceiving unit 2903.

The allocation unit 2901 is configured to allocate an SN to each MPDU inan A-MPDU.

The sending unit 2902 is configured to send the A-MPDU to a receivingdevice. Each MPDU in the A-MPDU carries the SN allocated by theallocation unit 2901.

The receiving unit 2903 is configured to receive an acknowledgementframe sent by the receiving device. The acknowledgement frame includesan indication field used to indicate a receiving state of each MPDU inthe A-MPDU sent by the sending unit 2902. Each bit in the indicationfield is used to indicate one MPDU in a sequence of SNs in the A-MPDU.

Optionally, the allocation unit 2901 is further configured to allocatethe SN to each MPDU in the A-MPDU when at least one MPDU in the A-MPDUis obtained by encapsulating a fragment of a MSDU).

Optionally, the SN is carried in a MAC header of the MPDU.

Optionally, when the acknowledgement frame uses a frame format of acompressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

Optionally, the acknowledgement frame further includes a fragmentindication field. The fragment indication field is used to indicate thatat least one MPDU in the A-MPDU is obtained by encapsulating a fragmentof an MSDU.

Based on Embodiment 4, the present disclosure further provides areceiving device 3000. The receiving device 3000 may use the methodprovided in the embodiment corresponding to FIG. 17. Referring to FIG.30, the receiving device 3000 includes a receiving unit 3001, adetermining unit 3002, and a sending unit 3003.

The receiving unit 3001 is configured to receive an A-MPDU sent by asending device. Each MPDU in the A-MPDU carries an SN of each MPDU.

The determining unit 3002 is configured to determine an acknowledgementframe. The acknowledgement frame includes an indication field used toindicate a receiving state of each MPDU in the A-MPDU received by thereceiving unit 3001. Each bit in the indication field is used toindicate one MPDU in a sequence of MPDU SNs in the A-MPDU.

The sending unit 3003 is configured to send the acknowledgement framedetermined by the determining unit 3002 to the sending device.

Optionally, the SN is carried in a MAC header of the MPDU.

Optionally, when the acknowledgement frame uses a frame format of acompressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

Optionally, the acknowledgement frame further includes a fragmentindication field. The fragment indication field is used to indicate thatat least one MPDU in the A-MPDU is obtained by encapsulating a fragmentof an MSDU.

It should be noted that unit division in this embodiment of the presentdisclosure is an example, is merely logical function division, and theremay be another division in actual implementation. In addition, functionunits in the embodiments of this application may be integrated into oneprocessing unit, or each of the units may exist alone physically, or twoor more units are integrated into one unit. The integrated unit may beimplemented in a form of hardware, or may be implemented in a form of asoftware function unit.

When the integrated unit is implemented in the form of a softwarefunction unit and sold or used as an independent product, the integratedunit may be stored in a computer-readable storage medium. Based on suchan understanding, the technical solutions of this applicationessentially, or the part contributing to the other approaches, or all orsome of the technical solutions may be implemented in a form of asoftware product. The computer software product is stored in a storagemedium and includes several instructions for instructing a computerdevice (which may be a personal computer, a server, a network device, orthe like) or a processor to perform all or some of the steps of themethods in the embodiments of the present application. The foregoingstorage medium includes any medium that can store program code, such asa USB flash drive, a removable hard disk, a ROM, a RAM, a magnetic disk,or an optical disc.

Based on Embodiment 4, the present disclosure further provides a sendingdevice 3100. The sending device 3100 may use the method provided in theembodiment corresponding to FIG. 17, and may be a device the same as thesending device 2900 shown in FIG. 29. Referring to FIG. 31, the sendingdevice 3100 includes a processor 3101, a transceiver 3102, a bus 3103,and a memory 3104.

The processor 3101, the transceiver 3102, and the memory 3104 areinterconnected using the bus 3103. The bus 3103 may be a PCI bus, anEISA bus, or the like. The bus 3103 may be classified into an addressbus, a data bus, a control bus, and the like. For ease of illustration,only one bold line is used in FIG. 31 to represent the bus 3103, which,however, does not mean that there is only one bus or only one type ofbus.

The processor 3101 is configured to allocate an SN to each MPDU in anA-MPDU.

The transceiver 3102 is configured to send the A-MPDU to a receivingdevice, where each MPDU in the A-MPDU carries the SN allocated by theprocessor 3101, and receive an acknowledgement frame sent by thereceiving device. The acknowledgement frame includes an indication fieldused to indicate a receiving state of each MPDU in the A-MPDU. Each bitin the indication field is used to indicate one MPDU in a sequence ofSNs in the A-MPDU.

Optionally, the processor 3101 is further configured to allocate the SNto each MPDU in the A-MPDU when at least one MPDU in the A-MPDU isobtained by encapsulating a fragment of an MSDU.

Optionally, the SN is carried in a MAC header of the MPDU.

Optionally, when the acknowledgement frame uses a frame format of acompressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

Optionally, the acknowledgement frame further includes a fragmentindication field. The fragment indication field is used to indicate thatat least one MPDU in the A-MPDU is obtained by encapsulating a fragmentof an MSDU.

The sending device 3100 further includes the memory 3104, which isconfigured to store a program and the like. Further, the program mayinclude program code. The program code includes a computer operationinstruction. The memory 3104 may include a RAM, and may further includea non-volatile memory, for example, at least one disk memory. Theprocessor 3101 executes the application program stored in the memory3104 to implement the receiving state indication method for an A-MPDU.

Based on Embodiment 4, the present disclosure further provides areceiving device 3200. The receiving device 3200 may use the methodprovided in the embodiment corresponding to FIG. 17, and may be a devicethe same as the receiving device 3000 shown in FIG. 30. Referring toFIG. 32, the receiving device 3200 includes a transceiver 3201, aprocessor 3202, a bus 3203, and a memory 3204.

The transceiver 3201, the processor 3202, and the memory 3204 areinterconnected using the bus 3203. The bus 3203 may be a PCI bus, anEISA bus, or the like. The bus 3203 may be classified into an addressbus, a data bus, a control bus, and the like. For ease of illustration,only one bold line is used in FIG. 32 to represent the bus 3203, which,however, does not mean that there is only one bus or only one type ofbus.

The transceiver 3201 is configured to receive an A-MPDU sent by asending device. Each MPDU in the A-MPDU carries an SN of each MPDU.

The processor 3202 is configured to determine an acknowledgement frame.The acknowledgement frame includes an indication field used to indicatea receiving state of each MPDU in the A-MPDU received by the transceiver3201. Each bit in the indication field is used to indicate one MPDU in asequence of MPDU SNs in the A-MPDU.

The transceiver 3201 is further configured to send the acknowledgementframe determined by the processor 3202 to the sending device.

Optionally, the SN is carried in a MAC header of the MPDU.

Optionally, when the acknowledgement frame uses a frame format of acompressed BA frame, the indication field included in theacknowledgement frame is a BA bitmap field in the compressed BA frame.

Optionally, the acknowledgement frame further includes a fragmentindication field. The fragment indication field is used to indicate thatat least one MPDU in the A-MPDU is obtained by encapsulating a fragmentof an MSDU.

Persons skilled in the art should understand that the embodiments of thepresent disclosure may be provided as a method, a system, or a computerprogram product. Therefore, the present disclosure may use a form ofhardware only embodiments, software only embodiments, or embodimentswith a combination of software and hardware. Moreover, the presentdisclosure may use a form of a computer program product that isimplemented on one or more computer-usable storage media (including butnot limited to a disk memory, a compact disc ROM (CD-ROM), an opticalmemory, and the like) that include computer-usable program code.

The present disclosure is described with reference to the flowchartsand/or block diagrams of the method, the device (system), and thecomputer program product according to the embodiments of the presentdisclosure. It should be understood that computer program instructionsmay be used to implement each process and/or each block in theflowcharts and/or the block diagrams and a combination of a processand/or a block in the flowcharts and/or the block diagrams. Thesecomputer program instructions may be provided for a general-purposecomputer, a dedicated computer, an embedded processor, or a processor ofany other programmable data processing device to generate a machine suchthat the instructions executed by a computer or a processor of any otherprogrammable data processing device generate an apparatus forimplementing a specific function in one or more processes in theflowcharts and/or in one or more blocks in the block diagrams.

These computer program instructions may be stored in a computer readablememory that can instruct the computer or any other programmable dataprocessing device to work in a specific manner such that theinstructions stored in the computer readable memory generate an artifactthat includes an instruction apparatus. The instruction apparatusimplements a specific function in one or more processes in theflowcharts and/or in one or more blocks in the block diagrams.

These computer program instructions may be loaded onto a computer oranother programmable data processing device such that a series ofoperations and steps are performed on the computer or the otherprogrammable device, thereby generating computer-implemented processing.Therefore, the instructions executed on the computer or the otherprogrammable device provide steps for implementing a specific functionin one or more processes in the flowcharts and/or in one or more blocksin the block diagrams.

Although some preferred embodiments of the present disclosure have beendescribed, persons skilled in the art can make changes and modificationsto these embodiments once they learn the basic inventive concept.Therefore, the following claims are intended to be construed as to coverthe preferred embodiments and all changes and modifications fallingwithin the scope of the present disclosure.

Obviously, persons skilled in the art can make various modifications andvariations to embodiments of the present disclosure without departingfrom the scope of the embodiments of the present disclosure. The presentdisclosure is intended to cover these modifications and variationsprovided that they fall within the scope of protection defined by thefollowing claims and their equivalent technologies.

What is claimed is:
 1. A receive end, comprising: a processor; and amemory storing instructions executable by the processor such that whenexecuted, cause the receive end to: receive an aggregate-media accesscontrol (MAC) protocol data unit (A-MPDU) comprising a MAC protocol dataunit (MPDU), wherein the MPDU comprises a sequence number (SN) and afragment number (FN), wherein the SN identifies a sequence number of aMAC service data unit (MSDU) having an MSDU fragment encapsulated intothe MPDU, and wherein the FN identifies a number of the MSDU fragment;and send an acknowledgement frame indicating a receiving state of theA-MPDU when all FN fields in the MPDU are 0, wherein the acknowledgementframe comprises a receiving state field including a blockacknowledgement bitmap field, and wherein each bit in the blockacknowledgement bitmap field corresponds to one SN and indicates areceiving state of the MPDU in a sequence of SNs in the A-MPDU.
 2. Thereceive end of claim 1, wherein the acknowledgement frame furthercomprises a fragment indication field, wherein the fragment indicationfield indicates that the acknowledgement frame is a second typeacknowledgement frame that is different from a first typeacknowledgement frame, wherein the first type acknowledgement framecomprises the receiving state field, and wherein each four bits in thereceiving state field correspond to one SN.
 3. The receive end of claim2, wherein, when the acknowledgement frame uses a frame format of amulti-user block acknowledgement frame or a compressed blockacknowledgement frame, the fragment indication field comprises one ormore bits of four reserved bits in a starting sequence control field ina block acknowledgement (BA) information field of the acknowledgementframe.
 4. The receive end according to claim 1, wherein the sequencenumber is carried in a MAC header of the MPDU.
 5. A receive end,comprising: a processor; and a memory storing instructions executable bythe processor such that when executed, cause the receive end to: receivean aggregate-media access control (MAC) protocol data unit (A-MPDU)comprising at least one MAC protocol data unit (MPDU), wherein the atleast one MPDU comprises a second MPDU including a MAC service data unit(MSDU) fragment, wherein the MSDU fragment is a segment of an MSDU,wherein the at least one MPDU comprises a sequence number (SN) and afragment number (FN), wherein the SN identifies a sequence number of theMSDU having the MSDU fragment encapsulated into the second MPDU, andwherein the FN identifies a number of the MSDU fragment; and send anacknowledgement frame indicating a receiving state of the A-MPDU when anFN field of the at least one MPDU is not 0, wherein the acknowledgementframe comprises a receiving state field indicating a receiving state ofeach MPDU in the A-MPDU in a sequence of SNs, wherein all bits of afixed quantity of bits in the receiving state field correspond to oneSN, and wherein one bit of the fixed quantity of bits in the receivingstate field indicates a receiving state of one MPDU in the A-MPDU. 6.The receive end of claim 5, wherein the one bit of the fixed quantity ofbits in the receiving state field indicates a receiving state of oneMPDU in a sequence of FNs.
 7. The receive end of claim 5, wherein thefixed quantity of bits in the receiving state field is 4 bits.
 8. Thereceive end of claim 5, wherein the acknowledgement frame furthercomprises a fragment indication field, wherein the fragment indicationfield indicates that the acknowledgement frame is a first typeacknowledgement frame which is different from a second typeacknowledgement frame, wherein the second type acknowledgement framecomprises a block acknowledgement bitmap field, and wherein each bit inthe block acknowledgement bitmap field corresponds to one SN.
 9. Thereceive end of claim 8, wherein, when the acknowledgement frame uses aframe format of a multi-user block acknowledgement frame or a compressedblock acknowledgement frame, the fragment indication field comprises oneor more bits of four reserved bits in a starting sequence control fieldin a block acknowledgement (BA) information field of the acknowledgementframe.
 10. The receive end of claim 5, wherein the fixed quantity ofbits is greater than or equal to a maximum value of an allowed quantityof MSDU fragments of one MSDU.
 11. The receive end according to claim 5,wherein the at least one MPDU further comprises a first MPDU, whereinthe first MPDU includes one MSDU.
 12. The receive end according to claim5, wherein the SN is carried in a MAC header of the MPDU.
 13. A transmitend comprising: a processor; and a memory storing instructionsexecutable by the processor such that when executed, cause the transmitend to: send an aggregate-media access control (MAC) protocol data unit(A-MPDU) to a receive end, wherein the A-MPDU comprises at least one MACprotocol data unit (MPDU), wherein the at least one MPDU comprises asecond MPDU including a MAC service data unit (MSDU) fragment, whereinthe MSDU fragment is a segment of an MSDU, wherein the at least one MPDUcomprises a SN identifying a sequence number of the MSDU having the MSDUfragment encapsulated into the second MPDU; and receiving anacknowledgement frame comprising an indication field indicating areceiving state of each MPDU in the A-MPDU in a sequence of SNs, whereinall bits of a fixed quantity of bits in the indication field correspondto one SN, and wherein one bit of the fixed quantity of bits in theindication field indicates a receiving state of one MPDU in the A-MPDU.14. The transmit end of claim 13, wherein the at least one MPDU furthercomprises a first MPDU, wherein the first MPDU comprises one MSDU. 15.The transmit end of claim 13, wherein the at least one MPDU furthercomprises a fragment number (FN) identifying a number of the MSDUfragment, and wherein one bit of the fixed quantity of bits indicates areceiving state of one MPDU in a sequence of FNs.
 16. The transmit endof claim 13, wherein the fixed quantity of bits is 4 bits.
 17. Thetransmit end of claim 13, wherein the SN is carried in a MAC header ofthe MPDU.
 18. The transmit end of claim 13, wherein the acknowledgementframe further comprises a fragment indication field, and the fragmentindication field indicating that the acknowledgement frame is a firsttype acknowledgement frame which is different from a second typeacknowledgement frame, wherein the second type acknowledgement framecomprises a block acknowledgement bitmap field, and each bit in theblock acknowledgement bitmap field corresponds to one SN.
 19. Thetransmit end according to claim 18, wherein, when the acknowledgementframe uses a frame format of a compressed block acknowledgement frame ora multi-user block acknowledgement frame, the fragment indication fieldcomprised in the acknowledgement frame is a block acknowledgement bitmapfield in the acknowledgement frame.